<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2023 Workiva-->
<!--r:302e9682-8834-4de0-a2cf-0c414a258dcb,g:26935dfa-903d-4758-9790-4544bb3559fd-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://acmrcsh.com/role/CoverPage" xlink:type="simple" xlink:href="acmr-20230630.xsd#CoverPage"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/CoverPage" xlink:type="extended" id="i186b2414734b4f23a3380cf4f59c4800_CoverPage">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_b68da614-3a6a-41bf-b465-dcd18c5e2b41" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentType_b68da614-3a6a-41bf-b465-dcd18c5e2b41" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentQuarterlyReport_986e2dab-adfd-498e-9999-af45d948830a" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentQuarterlyReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentQuarterlyReport_986e2dab-adfd-498e-9999-af45d948830a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_f373e865-ac42-4e3c-af3b-93eebfc4697d" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentPeriodEndDate_f373e865-ac42-4e3c-af3b-93eebfc4697d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentTransitionReport_2e19f29a-5c16-477c-ba2b-1fd06193e814" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentTransitionReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentTransitionReport_2e19f29a-5c16-477c-ba2b-1fd06193e814" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_3a6a7ca3-8935-4db8-bc53-ef184aab4f8c" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityFileNumber_3a6a7ca3-8935-4db8-bc53-ef184aab4f8c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_364b8a82-79ff-4a85-8241-7b8121ef6d68" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityRegistrantName_364b8a82-79ff-4a85-8241-7b8121ef6d68" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_e215f2e2-6b59-4260-aee9-3cce83bc9c5c" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityIncorporationStateCountryCode_e215f2e2-6b59-4260-aee9-3cce83bc9c5c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_8e06f3ce-38c0-402f-a5d5-fce4eea3c6e4" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityTaxIdentificationNumber_8e06f3ce-38c0-402f-a5d5-fce4eea3c6e4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_72378b31-33d4-40af-9c04-51014eee53f5" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityAddressAddressLine1_72378b31-33d4-40af-9c04-51014eee53f5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_41018e64-5ee0-48c1-bf19-aa20f1c6f804" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityAddressCityOrTown_41018e64-5ee0-48c1-bf19-aa20f1c6f804" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_d86c403b-92b6-41ff-ad5c-5fc9a94990f2" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityAddressStateOrProvince_d86c403b-92b6-41ff-ad5c-5fc9a94990f2" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_821bf62e-dd12-4ea5-9b64-9c4e99ff7e45" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityAddressPostalZipCode_821bf62e-dd12-4ea5-9b64-9c4e99ff7e45" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_a04de07a-14ca-4ab7-8829-1e39429c7c68" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_CityAreaCode_a04de07a-14ca-4ab7-8829-1e39429c7c68" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_e68fde7c-892f-47be-9130-ad109ae040dc" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_LocalPhoneNumber_e68fde7c-892f-47be-9130-ad109ae040dc" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_4a219b64-d507-489e-a986-69bc73ea253f" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_Security12bTitle_4a219b64-d507-489e-a986-69bc73ea253f" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_4455321d-96f1-4454-beea-64e002558776" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_TradingSymbol_4455321d-96f1-4454-beea-64e002558776" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_47fff769-9303-4fb8-8063-fc00cd362579" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_SecurityExchangeName_47fff769-9303-4fb8-8063-fc00cd362579" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCurrentReportingStatus_2029b132-d994-4c47-a511-95bfd11396cc" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityCurrentReportingStatus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityCurrentReportingStatus_2029b132-d994-4c47-a511-95bfd11396cc" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInteractiveDataCurrent_2a3c0c49-3258-43fa-a884-ff610f1985d6" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityInteractiveDataCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityInteractiveDataCurrent_2a3c0c49-3258-43fa-a884-ff610f1985d6" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFilerCategory_1adb7ece-d3c6-47a0-90c8-bec32177a22e" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityFilerCategory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityFilerCategory_1adb7ece-d3c6-47a0-90c8-bec32177a22e" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness_2140c443-48ec-42ce-b726-cda185e4cc3b" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntitySmallBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntitySmallBusiness_2140c443-48ec-42ce-b726-cda185e4cc3b" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_f3607160-88d5-453d-b807-cd2cf13462b7" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityEmergingGrowthCompany_f3607160-88d5-453d-b807-cd2cf13462b7" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityShellCompany_7bec852f-0c67-4e70-9319-0464ee30b274" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityShellCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityShellCompany_7bec852f-0c67-4e70-9319-0464ee30b274" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_39125bb6-9513-4b5a-bd4c-f69245203ac2" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_39125bb6-9513-4b5a-bd4c-f69245203ac2" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_a457ec73-bcba-4240-aca2-7aff1caac757" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_EntityCentralIndexKey_a457ec73-bcba-4240-aca2-7aff1caac757" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalYearFocus_3865d0d1-e56d-41cb-93ae-1cc38bf74f73" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentFiscalYearFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentFiscalYearFocus_3865d0d1-e56d-41cb-93ae-1cc38bf74f73" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_c0a11ee2-c9ce-4897-ad72-65ca3a0e3917" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_AmendmentFlag_c0a11ee2-c9ce-4897-ad72-65ca3a0e3917" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate_7493f174-1774-4e4b-a141-3fdc171204ce" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_CurrentFiscalYearEndDate_7493f174-1774-4e4b-a141-3fdc171204ce" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalPeriodFocus_93586a29-d23f-4b16-aa18-7a2954d53467" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentFiscalPeriodFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentFiscalPeriodFocus_93586a29-d23f-4b16-aa18-7a2954d53467" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_6d85d935-19e3-4497-9449-a789017e7870" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_39ba3b67-5d7b-46c7-9caf-57180ebb8c62" xlink:to="loc_dei_DocumentInformationTable_6d85d935-19e3-4497-9449-a789017e7870" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_ac454880-95d3-49b6-8367-9b7ac2a55903" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_6d85d935-19e3-4497-9449-a789017e7870" xlink:to="loc_us-gaap_StatementClassOfStockAxis_ac454880-95d3-49b6-8367-9b7ac2a55903" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_ac454880-95d3-49b6-8367-9b7ac2a55903_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_ac454880-95d3-49b6-8367-9b7ac2a55903" xlink:to="loc_us-gaap_ClassOfStockDomain_ac454880-95d3-49b6-8367-9b7ac2a55903_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_3164e391-eab8-4833-a0b0-c743200861a2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_ac454880-95d3-49b6-8367-9b7ac2a55903" xlink:to="loc_us-gaap_ClassOfStockDomain_3164e391-eab8-4833-a0b0-c743200861a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_b352cf5a-099a-4725-a9a4-db4f5e6d97f9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_3164e391-eab8-4833-a0b0-c743200861a2" xlink:to="loc_us-gaap_CommonClassAMember_b352cf5a-099a-4725-a9a4-db4f5e6d97f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_a7a98042-0bf3-4113-beee-a0bef381ab3a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_3164e391-eab8-4833-a0b0-c743200861a2" xlink:to="loc_us-gaap_CommonClassBMember_a7a98042-0bf3-4113-beee-a0bef381ab3a" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/CondensedConsolidatedBalanceSheets" xlink:type="simple" xlink:href="acmr-20230630.xsd#CondensedConsolidatedBalanceSheets"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/CondensedConsolidatedBalanceSheets" xlink:type="extended" id="i4a46418fd41f4d5fb7baad143b11aa79_CondensedConsolidatedBalanceSheets">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_9552cf67-c1ea-4efd-a37c-771338ec132a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9552cf67-c1ea-4efd-a37c-771338ec132a" xlink:to="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsCurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_7135e1ef-523f-4fb8-8629-18cdb5c94f36" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_7135e1ef-523f-4fb8-8629-18cdb5c94f36" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashCurrent_4d370fbd-b108-4736-bbec-86ff93fb0ea4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RestrictedCashCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_RestrictedCashCurrent_4d370fbd-b108-4736-bbec-86ff93fb0ea4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsAssetsCurrent_8f89dc08-202a-407e-a984-85bcd1062eef" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositsAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_DepositsAssetsCurrent_8f89dc08-202a-407e-a984-85bcd1062eef" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecuritiesCurrent_299ce319-1015-4e56-b42c-01fab4ab2067" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MarketableSecuritiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_MarketableSecuritiesCurrent_299ce319-1015-4e56-b42c-01fab4ab2067" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_5eddaf9d-c50f-443c-9e8d-79a6d6b5b091" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_5eddaf9d-c50f-443c-9e8d-79a6d6b5b091" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivablesNetCurrent_8e86f7c1-5817-4ed0-bb1c-bbd6fab4af3f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherReceivablesNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_OtherReceivablesNetCurrent_8e86f7c1-5817-4ed0-bb1c-bbd6fab4af3f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_9ace38ca-a6e1-4105-a46c-77734e7e15da" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_InventoryNet_9ace38ca-a6e1-4105-a46c-77734e7e15da" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseCurrent_3b4afb06-4e90-47e6-945d-23819200e517" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PrepaidExpenseCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_PrepaidExpenseCurrent_3b4afb06-4e90-47e6-945d-23819200e517" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_c9915c52-5ec2-4a25-aa4b-5576849cf46f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_67775977-abbf-4763-9cf3-1adef9cf7df3" xlink:to="loc_us-gaap_AssetsCurrent_c9915c52-5ec2-4a25-aa4b-5576849cf46f" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_43047e16-7a1d-4d55-93a9-f3002cb90aae" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_43047e16-7a1d-4d55-93a9-f3002cb90aae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LandUseRightNet_4db6d8a5-ae6b-43a1-9ba0-fab3a7cef308" xlink:href="acmr-20230630.xsd#acmr_LandUseRightNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_acmr_LandUseRightNet_4db6d8a5-ae6b-43a1-9ba0-fab3a7cef308" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_89daf802-9e48-4ed8-835c-90f7c8fdc5f1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_89daf802-9e48-4ed8-835c-90f7c8fdc5f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_79b558f6-089e-407d-8517-05894ae909a3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_79b558f6-089e-407d-8517-05894ae909a3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsAssetsNoncurrent_e651504b-d118-4b59-aaab-1da1f88ef847" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositsAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_DepositsAssetsNoncurrent_e651504b-d118-4b59-aaab-1da1f88ef847" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_6e785566-3248-43f1-a118-2b0b77f7a271" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredIncomeTaxAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_6e785566-3248-43f1-a118-2b0b77f7a271" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_c442a604-949c-40df-8c62-dd87ad63486b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_LongTermInvestments_c442a604-949c-40df-8c62-dd87ad63486b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_aea3c049-7585-4220-8ad2-f63d752a07e2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_aea3c049-7585-4220-8ad2-f63d752a07e2" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_6e3b7519-7cc4-473a-8c1f-ffbd202c179c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_b29903ba-3da6-42b5-968b-c4be979aff62" xlink:to="loc_us-gaap_Assets_6e3b7519-7cc4-473a-8c1f-ffbd202c179c" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9552cf67-c1ea-4efd-a37c-771338ec132a" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_d2c239c6-c771-433f-bf8b-d853a29a214a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_AccountsPayableCurrent_d2c239c6-c771-433f-bf8b-d853a29a214a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAccountsPayableAndAccruedLiabilities_271295b7-0577-4a32-aaf6-a771bd909599" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherAccountsPayableAndAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_OtherAccountsPayableAndAccruedLiabilities_271295b7-0577-4a32-aaf6-a771bd909599" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_9413a7b8-6acd-4812-b439-ae048cfa17d2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ContractWithCustomerLiabilityCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityCurrent_9413a7b8-6acd-4812-b439-ae048cfa17d2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_9f435db5-f34f-4699-9283-1bedc121c312" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_9f435db5-f34f-4699-9283-1bedc121c312" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeCurrent_07765488-1e70-43c6-8460-07ed9361a8cb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredIncomeCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_DeferredIncomeCurrent_07765488-1e70-43c6-8460-07ed9361a8cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermBorrowings_05f260a2-86c9-436b-812a-bbef9d3e5b92" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_ShortTermBorrowings_05f260a2-86c9-436b-812a-bbef9d3e5b92" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_11daba14-f429-4944-b685-98513a3098cc" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_LongTermDebtCurrent_11daba14-f429-4944-b685-98513a3098cc" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedIncomeTaxesCurrent_614d5d18-83e5-4105-aadb-2aed7f8f86c4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccruedIncomeTaxesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_AccruedIncomeTaxesCurrent_614d5d18-83e5-4105-aadb-2aed7f8f86c4" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_IncomeTaxesCurrentPayableAndDeferredTaxLiabilities_c87b007d-7b9b-4c7f-80e5-9dcb9aba2c53" xlink:href="acmr-20230630.xsd#acmr_IncomeTaxesCurrentPayableAndDeferredTaxLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_acmr_IncomeTaxesCurrentPayableAndDeferredTaxLiabilities_c87b007d-7b9b-4c7f-80e5-9dcb9aba2c53" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_ff243928-e099-45c0-a5d5-11fcec10945f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_3cef2e0d-59c3-4f05-91e7-8605e20b76ae" xlink:to="loc_us-gaap_LiabilitiesCurrent_ff243928-e099-45c0-a5d5-11fcec10945f" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_0dae6fdd-2792-4688-83f3-20a3b14299be" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_0dae6fdd-2792-4688-83f3-20a3b14299be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_aef72d32-e076-4bf9-abe5-468a4df63595" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_aef72d32-e076-4bf9-abe5-468a4df63595" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_fad04833-367c-4263-885b-40a9936b0a91" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_fad04833-367c-4263-885b-40a9936b0a91" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_1f301347-7400-495c-9995-71ed55accd79" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_Liabilities_1f301347-7400-495c-9995-71ed55accd79" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_b7e8f797-137c-43cb-9ad8-bcc51fe4f005" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_CommitmentsAndContingencies_b7e8f797-137c-43cb-9ad8-bcc51fe4f005" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_2254bfbc-6500-4281-b7d1-40e62038438d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_CommonStockValue_2254bfbc-6500-4281-b7d1-40e62038438d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_fe9bf986-0df9-4a90-a8bb-759002e292e8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_AdditionalPaidInCapital_fe9bf986-0df9-4a90-a8bb-759002e292e8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_89db2541-4ce2-4073-a7c7-d790093c1b25" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_89db2541-4ce2-4073-a7c7-d790093c1b25" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance_540d3d20-1a30-47f8-b24a-cd2922273fe8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance_540d3d20-1a30-47f8-b24a-cd2922273fe8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_2a553a14-aaea-4304-a824-b42261269668" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_2a553a14-aaea-4304-a824-b42261269668" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_2740d2f1-6c49-458d-802c-df936536bcd3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_StockholdersEquity_2740d2f1-6c49-458d-802c-df936536bcd3" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterest_abf8acfd-03d9-47b7-9b31-010f3cc6a577" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MinorityInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_MinorityInterest_abf8acfd-03d9-47b7-9b31-010f3cc6a577" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_91aa95ec-6cc0-4d0f-a557-2a079ab65b49" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_895e61e2-457d-4e7e-ad6e-80d8e2d23331" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_91aa95ec-6cc0-4d0f-a557-2a079ab65b49" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_5779a960-00ea-4963-b9b7-1fcbe4ef7293" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_6c059284-d54d-4192-af8a-837b4d17d8b9" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_5779a960-00ea-4963-b9b7-1fcbe4ef7293" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_6383e682-fd7f-4c3c-965a-b3981cff586f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_9552cf67-c1ea-4efd-a37c-771338ec132a" xlink:to="loc_us-gaap_StatementTable_6383e682-fd7f-4c3c-965a-b3981cff586f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_08696b36-7fe1-4364-964e-3d19e1146221" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_6383e682-fd7f-4c3c-965a-b3981cff586f" xlink:to="loc_us-gaap_StatementClassOfStockAxis_08696b36-7fe1-4364-964e-3d19e1146221" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_08696b36-7fe1-4364-964e-3d19e1146221_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_08696b36-7fe1-4364-964e-3d19e1146221" xlink:to="loc_us-gaap_ClassOfStockDomain_08696b36-7fe1-4364-964e-3d19e1146221_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_d10114b4-863c-42d0-a309-ad3740643a92" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_08696b36-7fe1-4364-964e-3d19e1146221" xlink:to="loc_us-gaap_ClassOfStockDomain_d10114b4-863c-42d0-a309-ad3740643a92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_beae0e3b-4b01-4f7a-b401-4c27697f63bf" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_d10114b4-863c-42d0-a309-ad3740643a92" xlink:to="loc_us-gaap_CommonClassAMember_beae0e3b-4b01-4f7a-b401-4c27697f63bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_b7cbf902-da19-4724-8543-7993f72dff31" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_d10114b4-863c-42d0-a309-ad3740643a92" xlink:to="loc_us-gaap_CommonClassBMember_b7cbf902-da19-4724-8543-7993f72dff31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c12ddba2-e69a-4856-b02d-3a039fd91b58" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_6383e682-fd7f-4c3c-965a-b3981cff586f" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c12ddba2-e69a-4856-b02d-3a039fd91b58" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_c12ddba2-e69a-4856-b02d-3a039fd91b58_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c12ddba2-e69a-4856-b02d-3a039fd91b58" xlink:to="loc_us-gaap_RelatedPartyDomain_c12ddba2-e69a-4856-b02d-3a039fd91b58_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_c1975fd2-3a9c-476f-8504-d3adb6d658d6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_c12ddba2-e69a-4856-b02d-3a039fd91b58" xlink:to="loc_us-gaap_RelatedPartyDomain_c1975fd2-3a9c-476f-8504-d3adb6d658d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_cbbe1ee1-ae65-4e28-8055-dc6e8c918e2e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_c1975fd2-3a9c-476f-8504-d3adb6d658d6" xlink:to="loc_us-gaap_RelatedPartyMember_cbbe1ee1-ae65-4e28-8055-dc6e8c918e2e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonrelatedPartyMember_d5e5f354-251f-4ea7-9750-9c9994bd94b8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NonrelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_c1975fd2-3a9c-476f-8504-d3adb6d658d6" xlink:to="loc_us-gaap_NonrelatedPartyMember_d5e5f354-251f-4ea7-9750-9c9994bd94b8" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/CondensedConsolidatedStatementsofChangesinEquity" xlink:type="simple" xlink:href="acmr-20230630.xsd#CondensedConsolidatedStatementsofChangesinEquity"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/CondensedConsolidatedStatementsofChangesinEquity" xlink:type="extended" id="i7768ae4116c34613aa9ad2985362f4e2_CondensedConsolidatedStatementsofChangesinEquity">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_551c41b7-8c01-43c4-b9ae-ebe7288be595" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_551c41b7-8c01-43c4-b9ae-ebe7288be595" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_aa74b202-5b2f-44fe-9dc1-d157c02c187d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_SharesOutstanding_aa74b202-5b2f-44fe-9dc1-d157c02c187d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_196d4d67-167a-4577-921f-c1621ca9347b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_196d4d67-167a-4577-921f-c1621ca9347b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment_39aec169-a10a-4f74-985e-1fbc0fa592fc" xlink:href="acmr-20230630.xsd#acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment_39aec169-a10a-4f74-985e-1fbc0fa592fc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_47623c04-d0e1-4ef3-a51e-901d0e661b13" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_ProfitLoss_47623c04-d0e1-4ef3-a51e-901d0e661b13" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_b66dc849-6658-48a2-ab2b-8341ccfb27a7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_b66dc849-6658-48a2-ab2b-8341ccfb27a7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_aab6e256-d8bc-4eda-b87b-75e8ad531531" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_aab6e256-d8bc-4eda-b87b-75e8ad531531" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_093dd9ce-cfc5-47c2-b233-09bbd04e95bd" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_093dd9ce-cfc5-47c2-b233-09bbd04e95bd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_DividendsCommonStockCashDeclared_090cb76f-da87-4a56-b960-4ab9495ecfff" xlink:href="acmr-20230630.xsd#acmr_DividendsCommonStockCashDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_acmr_DividendsCommonStockCashDeclared_090cb76f-da87-4a56-b960-4ab9495ecfff" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_d416094a-df0d-4a76-8aea-97e5b0bb363a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_d416094a-df0d-4a76-8aea-97e5b0bb363a" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_1b973063-b3f8-4961-a760-03f7020784d9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_1b973063-b3f8-4961-a760-03f7020784d9" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_41599977-ffd3-4223-b099-b4ab9a35e11e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfUnits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_246bb2f0-476a-4ed3-83b9-b660c03780c0" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_41599977-ffd3-4223-b099-b4ab9a35e11e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_7738ef2f-373f-497d-b933-b586c2d88ee0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_76ace6c7-dbaf-443c-9fa9-c390fd7b2bc4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment_ac4f937e-ed13-468e-8fa9-b0d54f3a38cf" xlink:href="acmr-20230630.xsd#acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_f4ec0634-7cea-438d-ab12-a8ea2956b83b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_551c41b7-8c01-43c4-b9ae-ebe7288be595" xlink:to="loc_us-gaap_StatementTable_f4ec0634-7cea-438d-ab12-a8ea2956b83b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_918da49a-3adc-49a9-ae3e-69f6307c5ab1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_f4ec0634-7cea-438d-ab12-a8ea2956b83b" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_918da49a-3adc-49a9-ae3e-69f6307c5ab1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_918da49a-3adc-49a9-ae3e-69f6307c5ab1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_918da49a-3adc-49a9-ae3e-69f6307c5ab1" xlink:to="loc_us-gaap_EquityComponentDomain_918da49a-3adc-49a9-ae3e-69f6307c5ab1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_918da49a-3adc-49a9-ae3e-69f6307c5ab1" xlink:to="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_bd950fb6-5374-4af7-8655-75763d304374" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:to="loc_us-gaap_CommonStockMember_bd950fb6-5374-4af7-8655-75763d304374" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_7940f134-7140-475a-a1e9-b5cc5638440c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_7940f134-7140-475a-a1e9-b5cc5638440c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_9b2e9456-5480-4c41-ad36-104db01e825b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:to="loc_us-gaap_RetainedEarningsMember_9b2e9456-5480-4c41-ad36-104db01e825b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAppropriatedMember_ba0ba323-8169-40dc-bd12-8f27904f768c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsAppropriatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:to="loc_us-gaap_RetainedEarningsAppropriatedMember_ba0ba323-8169-40dc-bd12-8f27904f768c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_294743aa-11b3-4084-8627-7eec7fa91c22" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_294743aa-11b3-4084-8627-7eec7fa91c22" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_0007f1c3-6537-47dc-8ddb-f2f07f6c0db5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_c656d090-6fec-4873-b41f-87f3278cfba4" xlink:to="loc_us-gaap_NoncontrollingInterestMember_0007f1c3-6537-47dc-8ddb-f2f07f6c0db5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_c23ee5bb-3005-455d-92be-c1f082073981" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_f4ec0634-7cea-438d-ab12-a8ea2956b83b" xlink:to="loc_us-gaap_StatementClassOfStockAxis_c23ee5bb-3005-455d-92be-c1f082073981" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_c23ee5bb-3005-455d-92be-c1f082073981_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_c23ee5bb-3005-455d-92be-c1f082073981" xlink:to="loc_us-gaap_ClassOfStockDomain_c23ee5bb-3005-455d-92be-c1f082073981_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_6e9dbc56-f098-44e0-b33b-d629ee5db2d0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_c23ee5bb-3005-455d-92be-c1f082073981" xlink:to="loc_us-gaap_ClassOfStockDomain_6e9dbc56-f098-44e0-b33b-d629ee5db2d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_ec114aeb-e2df-4e14-adf6-339db6946968" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_6e9dbc56-f098-44e0-b33b-d629ee5db2d0" xlink:to="loc_us-gaap_CommonClassAMember_ec114aeb-e2df-4e14-adf6-339db6946968" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_43bb7f64-1b23-46b7-9a4c-c8699a0ca7fa" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_6e9dbc56-f098-44e0-b33b-d629ee5db2d0" xlink:to="loc_us-gaap_CommonClassBMember_43bb7f64-1b23-46b7-9a4c-c8699a0ca7fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_435ed1a1-5c78-4984-b8a8-e3922155e5b6" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_f4ec0634-7cea-438d-ab12-a8ea2956b83b" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_435ed1a1-5c78-4984-b8a8-e3922155e5b6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_435ed1a1-5c78-4984-b8a8-e3922155e5b6_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_435ed1a1-5c78-4984-b8a8-e3922155e5b6" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_435ed1a1-5c78-4984-b8a8-e3922155e5b6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_2423b0b2-2572-44b8-99f5-94d771550aee" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_435ed1a1-5c78-4984-b8a8-e3922155e5b6" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_2423b0b2-2572-44b8-99f5-94d771550aee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember_1980a932-5677-4004-86c9-02697eb040f7" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_2423b0b2-2572-44b8-99f5-94d771550aee" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember_1980a932-5677-4004-86c9-02697eb040f7" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/DESCRIPTIONOFBUSINESSDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#DESCRIPTIONOFBUSINESSDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/DESCRIPTIONOFBUSINESSDetails" xlink:type="extended" id="ie842a1fcfc9946269b83288958c4fd5b_DESCRIPTIONOFBUSINESSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_fcd16a64-6361-4723-9de3-917ba9f09b65" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:href="acmr-20230630.xsd#acmr_BusinessDescriptionAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_fcd16a64-6361-4723-9de3-917ba9f09b65" xlink:to="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_BusinessAcquisitionPercentageOfEquityInterestsAcquired_4da1e437-af22-4390-837f-c3cacfd465ba" xlink:href="acmr-20230630.xsd#acmr_BusinessAcquisitionPercentageOfEquityInterestsAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_acmr_BusinessAcquisitionPercentageOfEquityInterestsAcquired_4da1e437-af22-4390-837f-c3cacfd465ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfInterestInConsolidatedSubsidiaries_eb226fb3-49d6-4363-b225-bc3b76777c2c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromDivestitureOfInterestInConsolidatedSubsidiaries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_ProceedsFromDivestitureOfInterestInConsolidatedSubsidiaries_eb226fb3-49d6-4363-b225-bc3b76777c2c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_47867c18-e2d6-4f1c-8860-4541cbd8e3ec" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_47867c18-e2d6-4f1c-8860-4541cbd8e3ec" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_PercentageAmountOfSharesOfferedFromSharesOutstanding_e337710d-63ac-4ca2-9355-fba370de7885" xlink:href="acmr-20230630.xsd#acmr_PercentageAmountOfSharesOfferedFromSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_acmr_PercentageAmountOfSharesOfferedFromSharesOutstanding_e337710d-63ac-4ca2-9355-fba370de7885" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_eb2942e4-742a-44ea-af3a-a0cc9c6270a3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_eb2942e4-742a-44ea-af3a-a0cc9c6270a3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_e4b255b1-98da-4290-be9a-4e15af086082" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_e4b255b1-98da-4290-be9a-4e15af086082" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceInitialPublicOffering_76d90fd1-b800-4ec7-afdd-7d9a53ae4a55" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromIssuanceInitialPublicOffering"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_ProceedsFromIssuanceInitialPublicOffering_76d90fd1-b800-4ec7-afdd-7d9a53ae4a55" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_7fc2c706-1dcd-4e7d-b046-b8da77eb9cbd" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_7fc2c706-1dcd-4e7d-b046-b8da77eb9cbd" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_78d7ee92-011d-4e75-b7f9-b77e2002c970" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_78d7ee92-011d-4e75-b7f9-b77e2002c970" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_AdditionalSharesReservedForIssuanceAsDividends_36564a85-7a9a-473a-89a2-bffe86cd3d0f" xlink:href="acmr-20230630.xsd#acmr_AdditionalSharesReservedForIssuanceAsDividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_acmr_AdditionalSharesReservedForIssuanceAsDividends_36564a85-7a9a-473a-89a2-bffe86cd3d0f" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NameOfSubsidiary_b8e374dc-0861-4553-ab9f-7c961ec5de5f" xlink:href="acmr-20230630.xsd#acmr_NameOfSubsidiary"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_acmr_NameOfSubsidiary_b8e374dc-0861-4553-ab9f-7c961ec5de5f" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NameOfDateOfIncorporation_a5032bdb-46f6-4caa-b73a-0c9ff1dcc68f" xlink:href="acmr-20230630.xsd#acmr_NameOfDateOfIncorporation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_acmr_NameOfDateOfIncorporation_a5032bdb-46f6-4caa-b73a-0c9ff1dcc68f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SubsidiariesOwnershipPercentage_c62bd3ad-6e2c-4804-bfe9-42805d979b16" xlink:href="acmr-20230630.xsd#acmr_SubsidiariesOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_acmr_SubsidiariesOwnershipPercentage_c62bd3ad-6e2c-4804-bfe9-42805d979b16" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_9bcb9c36-7456-485f-b81e-65cdabf5c31c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_BusinessDescriptionAbstract_53bbf618-5f20-4d23-aafb-7aaed829a70f" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_9bcb9c36-7456-485f-b81e-65cdabf5c31c" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_d8d03ca5-16ba-40d3-adf4-3b6643c04012" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_fcd16a64-6361-4723-9de3-917ba9f09b65" xlink:to="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_d8d03ca5-16ba-40d3-adf4-3b6643c04012" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_e3781965-aa64-43d1-9d68-afa206c95870" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_d8d03ca5-16ba-40d3-adf4-3b6643c04012" xlink:to="loc_srt_ConsolidatedEntitiesAxis_e3781965-aa64-43d1-9d68-afa206c95870" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_e3781965-aa64-43d1-9d68-afa206c95870_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_e3781965-aa64-43d1-9d68-afa206c95870" xlink:to="loc_srt_ConsolidatedEntitiesDomain_e3781965-aa64-43d1-9d68-afa206c95870_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_e3781965-aa64-43d1-9d68-afa206c95870" xlink:to="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchShanghaiIncMember_e0c62627-92ec-46dd-a3cb-9c681af6b5a0" xlink:href="acmr-20230630.xsd#acmr_ACMResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchShanghaiIncMember_e0c62627-92ec-46dd-a3cb-9c681af6b5a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchWuxiIncMember_b413bb3d-1017-4184-bb58-40be54fb99ae" xlink:href="acmr-20230630.xsd#acmr_ACMResearchWuxiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchWuxiIncMember_b413bb3d-1017-4184-bb58-40be54fb99ae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_CleanChipTechnologiesLimitedMember_f8f37e89-180b-40f7-a640-933fbd33dce5" xlink:href="acmr-20230630.xsd#acmr_CleanChipTechnologiesLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_CleanChipTechnologiesLimitedMember_f8f37e89-180b-40f7-a640-933fbd33dce5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchKoreaCOLTDMember_130c04d3-28d5-43e3-977f-3a82e4269389" xlink:href="acmr-20230630.xsd#acmr_ACMResearchKoreaCOLTDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchKoreaCOLTDMember_130c04d3-28d5-43e3-977f-3a82e4269389" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengweiResearchShanghaiIncMember_66d61b3e-00d9-424b-8c71-413b509698ee" xlink:href="acmr-20230630.xsd#acmr_ShengweiResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ShengweiResearchShanghaiIncMember_66d61b3e-00d9-424b-8c71-413b509698ee" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchCAIncMember_ecf21302-93e5-4030-b45c-de1366473a8b" xlink:href="acmr-20230630.xsd#acmr_ACMResearchCAIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchCAIncMember_ecf21302-93e5-4030-b45c-de1366473a8b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchCaymanIncMember_cc43dced-74cb-460c-94f8-7a4cec1e669e" xlink:href="acmr-20230630.xsd#acmr_ACMResearchCaymanIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchCaymanIncMember_cc43dced-74cb-460c-94f8-7a4cec1e669e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchSingaporePTELTDMember_3d9a945a-7077-4df7-b390-c2b018bd3ab3" xlink:href="acmr-20230630.xsd#acmr_ACMResearchSingaporePTELTDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchSingaporePTELTDMember_3d9a945a-7077-4df7-b390-c2b018bd3ab3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchBeijingIncMember_ff8487b9-a47d-485f-b822-3c96a6ec4e37" xlink:href="acmr-20230630.xsd#acmr_ACMResearchBeijingIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMResearchBeijingIncMember_ff8487b9-a47d-485f-b822-3c96a6ec4e37" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_HangukACMCOLTDMember_f68b044b-2526-4f2b-8a50-6e50dbd650ec" xlink:href="acmr-20230630.xsd#acmr_HangukACMCOLTDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_HangukACMCOLTDMember_f68b044b-2526-4f2b-8a50-6e50dbd650ec" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_YushengMicroSemiconductorShanghaiCoLtdMember_e93788bc-3960-4e92-8157-e67647af68e9" xlink:href="acmr-20230630.xsd#acmr_YushengMicroSemiconductorShanghaiCoLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_YushengMicroSemiconductorShanghaiCoLtdMember_e93788bc-3960-4e92-8157-e67647af68e9" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMWooliMicroelectronicsShanghaiCoLtdMember_036ce078-9a26-4ac5-b449-d3decfa3bd02" xlink:href="acmr-20230630.xsd#acmr_ACMWooliMicroelectronicsShanghaiCoLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7da8b120-5710-4200-a40c-59b7df574d60" xlink:to="loc_acmr_ACMWooliMicroelectronicsShanghaiCoLtdMember_036ce078-9a26-4ac5-b449-d3decfa3bd02" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_71b388c8-a8f6-4385-9566-50a2c837fac8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_d8d03ca5-16ba-40d3-adf4-3b6643c04012" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_71b388c8-a8f6-4385-9566-50a2c837fac8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_71b388c8-a8f6-4385-9566-50a2c837fac8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_71b388c8-a8f6-4385-9566-50a2c837fac8" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_71b388c8-a8f6-4385-9566-50a2c837fac8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_69e09e21-0fac-4159-b9f6-efe0c4673722" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_71b388c8-a8f6-4385-9566-50a2c837fac8" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_69e09e21-0fac-4159-b9f6-efe0c4673722" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IPOMember_64426650-636b-4324-ba90-18e1ad66bc7e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IPOMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_69e09e21-0fac-4159-b9f6-efe0c4673722" xlink:to="loc_us-gaap_IPOMember_64426650-636b-4324-ba90-18e1ad66bc7e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_5e3d569c-d5ca-44db-82bb-089dba67d537" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_d8d03ca5-16ba-40d3-adf4-3b6643c04012" xlink:to="loc_us-gaap_StatementClassOfStockAxis_5e3d569c-d5ca-44db-82bb-089dba67d537" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_5e3d569c-d5ca-44db-82bb-089dba67d537_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_5e3d569c-d5ca-44db-82bb-089dba67d537" xlink:to="loc_us-gaap_ClassOfStockDomain_5e3d569c-d5ca-44db-82bb-089dba67d537_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_0a394123-c3d6-4adf-973d-986aae89bbe5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_5e3d569c-d5ca-44db-82bb-089dba67d537" xlink:to="loc_us-gaap_ClassOfStockDomain_0a394123-c3d6-4adf-973d-986aae89bbe5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_f93e401b-407a-4bb8-8307-7d14f4ae5602" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_0a394123-c3d6-4adf-973d-986aae89bbe5" xlink:to="loc_us-gaap_CommonClassAMember_f93e401b-407a-4bb8-8307-7d14f4ae5602" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_d7d73a53-0cdf-4e97-9451-ea26c76f8602" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_0a394123-c3d6-4adf-973d-986aae89bbe5" xlink:to="loc_us-gaap_CommonClassBMember_d7d73a53-0cdf-4e97-9451-ea26c76f8602" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_21733be5-580b-41f5-87ae-dbcdc29c0578" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_d8d03ca5-16ba-40d3-adf4-3b6643c04012" xlink:to="loc_us-gaap_AwardTypeAxis_21733be5-580b-41f5-87ae-dbcdc29c0578" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_21733be5-580b-41f5-87ae-dbcdc29c0578_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_21733be5-580b-41f5-87ae-dbcdc29c0578" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_21733be5-580b-41f5-87ae-dbcdc29c0578_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_ed3fa66d-08d8-4b8f-a33b-154333769697" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_21733be5-580b-41f5-87ae-dbcdc29c0578" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_ed3fa66d-08d8-4b8f-a33b-154333769697" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_a7db9abc-d723-4897-841e-642e154c8ead" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_ed3fa66d-08d8-4b8f-a33b-154333769697" xlink:to="loc_us-gaap_EmployeeStockOptionMember_a7db9abc-d723-4897-841e-642e154c8ead" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESNewRestrictionsbyUSDepartmentofCommerceforPRCbasedSemiconductorProducersDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESNewRestrictionsbyUSDepartmentofCommerceforPRCbasedSemiconductorProducersDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESNewRestrictionsbyUSDepartmentofCommerceforPRCbasedSemiconductorProducersDetails" xlink:type="extended" id="i4f94de74b45d4dceb5ec25cc846d26c5_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESNewRestrictionsbyUSDepartmentofCommerceforPRCbasedSemiconductorProducersDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_7e754407-7a5c-42e3-9e48-65b389c1ae29" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NewRestrictionsByUSDepartmentOfCommerceForPRCBasedSemiconductorProducersAbstract_cf49f35d-ea96-45c5-8217-ef1419d3eb78" xlink:href="acmr-20230630.xsd#acmr_NewRestrictionsByUSDepartmentOfCommerceForPRCBasedSemiconductorProducersAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_7e754407-7a5c-42e3-9e48-65b389c1ae29" xlink:to="loc_acmr_NewRestrictionsByUSDepartmentOfCommerceForPRCBasedSemiconductorProducersAbstract_cf49f35d-ea96-45c5-8217-ef1419d3eb78" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_6fc2fabf-b0b8-448a-a688-816c6bcfa94f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_NewRestrictionsByUSDepartmentOfCommerceForPRCBasedSemiconductorProducersAbstract_cf49f35d-ea96-45c5-8217-ef1419d3eb78" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_6fc2fabf-b0b8-448a-a688-816c6bcfa94f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_5cab2205-e1fb-47d2-bf6f-3ab61ceb5895" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_7e754407-7a5c-42e3-9e48-65b389c1ae29" xlink:to="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_5cab2205-e1fb-47d2-bf6f-3ab61ceb5895" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_e7e8a6da-aff8-4237-a786-dce76390f40b" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_5cab2205-e1fb-47d2-bf6f-3ab61ceb5895" xlink:to="loc_srt_ConsolidatedEntitiesAxis_e7e8a6da-aff8-4237-a786-dce76390f40b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_e7e8a6da-aff8-4237-a786-dce76390f40b_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_e7e8a6da-aff8-4237-a786-dce76390f40b" xlink:to="loc_srt_ConsolidatedEntitiesDomain_e7e8a6da-aff8-4237-a786-dce76390f40b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_4c7219b4-9ac5-4167-b12b-7993dac20362" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_e7e8a6da-aff8-4237-a786-dce76390f40b" xlink:to="loc_srt_ConsolidatedEntitiesDomain_4c7219b4-9ac5-4167-b12b-7993dac20362" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_TheHualiHuahongGroupMember_c7f7bd6d-6471-4e2a-9b9e-b06bf8496813" xlink:href="acmr-20230630.xsd#acmr_TheHualiHuahongGroupMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_4c7219b4-9ac5-4167-b12b-7993dac20362" xlink:to="loc_acmr_TheHualiHuahongGroupMember_c7f7bd6d-6471-4e2a-9b9e-b06bf8496813" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_YangtzeMemoryTechnologiesMember_3e9c24e7-d692-4c65-95c2-24b0cae2423a" xlink:href="acmr-20230630.xsd#acmr_YangtzeMemoryTechnologiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_4c7219b4-9ac5-4167-b12b-7993dac20362" xlink:to="loc_acmr_YangtzeMemoryTechnologiesMember_3e9c24e7-d692-4c65-95c2-24b0cae2423a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SemiconductorManufacturingInternationalCorpMember_ed5a19d7-cdf4-4145-ad39-284047509452" xlink:href="acmr-20230630.xsd#acmr_SemiconductorManufacturingInternationalCorpMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_4c7219b4-9ac5-4167-b12b-7993dac20362" xlink:to="loc_acmr_SemiconductorManufacturingInternationalCorpMember_ed5a19d7-cdf4-4145-ad39-284047509452" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a4b7641-3475-4a61-a87d-08f4ff0deda1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_5cab2205-e1fb-47d2-bf6f-3ab61ceb5895" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a4b7641-3475-4a61-a87d-08f4ff0deda1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5a4b7641-3475-4a61-a87d-08f4ff0deda1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a4b7641-3475-4a61-a87d-08f4ff0deda1" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5a4b7641-3475-4a61-a87d-08f4ff0deda1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5442583d-8794-4e97-8d25-5924035c776d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a4b7641-3475-4a61-a87d-08f4ff0deda1" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5442583d-8794-4e97-8d25-5924035c776d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_4f746473-31de-4f1e-a6c1-6144ff61a398" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5442583d-8794-4e97-8d25-5924035c776d" xlink:to="loc_us-gaap_SalesRevenueNetMember_4f746473-31de-4f1e-a6c1-6144ff61a398" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_b800718d-2492-4fd1-ac03-be813d76da3e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_5cab2205-e1fb-47d2-bf6f-3ab61ceb5895" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_b800718d-2492-4fd1-ac03-be813d76da3e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_b800718d-2492-4fd1-ac03-be813d76da3e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_b800718d-2492-4fd1-ac03-be813d76da3e" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_b800718d-2492-4fd1-ac03-be813d76da3e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_cc2be125-e6a0-4999-bda8-c90ec5ce9c3e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_b800718d-2492-4fd1-ac03-be813d76da3e" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_cc2be125-e6a0-4999-bda8-c90ec5ce9c3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_e97ec1b6-79f6-431b-9221-86755bc3c6a4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_cc2be125-e6a0-4999-bda8-c90ec5ce9c3e" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_e97ec1b6-79f6-431b-9221-86755bc3c6a4" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESUseofEstimatesDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESUseofEstimatesDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESUseofEstimatesDetails" xlink:type="extended" id="i7a21dcb96ebb430e8d6f279095ce4317_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESUseofEstimatesDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_e646fa60-9e29-428d-bbbf-7b353e8a38b4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ImmaterialErrorCorrectionAmount_53bd5e6d-f7ed-406c-8ad0-5b77f39e1e79" xlink:href="acmr-20230630.xsd#acmr_ImmaterialErrorCorrectionAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e646fa60-9e29-428d-bbbf-7b353e8a38b4" xlink:to="loc_acmr_ImmaterialErrorCorrectionAmount_53bd5e6d-f7ed-406c-8ad0-5b77f39e1e79" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_4ff70f1f-9e19-414f-9c8e-57689a55e1da" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e646fa60-9e29-428d-bbbf-7b353e8a38b4" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_4ff70f1f-9e19-414f-9c8e-57689a55e1da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_ef37f41d-de1c-4967-a3e0-e116e414a0a3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e646fa60-9e29-428d-bbbf-7b353e8a38b4" xlink:to="loc_us-gaap_EquityMethodInvestments_ef37f41d-de1c-4967-a3e0-e116e414a0a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_79329224-bc25-444e-b698-6087383bbdfa" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e646fa60-9e29-428d-bbbf-7b353e8a38b4" xlink:to="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_79329224-bc25-444e-b698-6087383bbdfa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_e4c21c67-34e7-4bae-89fb-18d5d9440423" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_e646fa60-9e29-428d-bbbf-7b353e8a38b4" xlink:to="loc_us-gaap_StatementTable_e4c21c67-34e7-4bae-89fb-18d5d9440423" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAxis_4a2c1880-f4e6-4092-8515-06cf73266c61" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RestatementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_e4c21c67-34e7-4bae-89fb-18d5d9440423" xlink:to="loc_srt_RestatementAxis_4a2c1880-f4e6-4092-8515-06cf73266c61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_4a2c1880-f4e6-4092-8515-06cf73266c61_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RestatementAxis_4a2c1880-f4e6-4092-8515-06cf73266c61" xlink:to="loc_srt_RestatementDomain_4a2c1880-f4e6-4092-8515-06cf73266c61_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_78ac22bb-5a96-4771-9aef-77afd589778c" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RestatementAxis_4a2c1880-f4e6-4092-8515-06cf73266c61" xlink:to="loc_srt_RestatementDomain_78ac22bb-5a96-4771-9aef-77afd589778c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RevisionOfPriorPeriodErrorCorrectionAdjustmentMember_0622f1d9-45dd-4734-82c9-b311848cb3e6" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RevisionOfPriorPeriodErrorCorrectionAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RestatementDomain_78ac22bb-5a96-4771-9aef-77afd589778c" xlink:to="loc_srt_RevisionOfPriorPeriodErrorCorrectionAdjustmentMember_0622f1d9-45dd-4734-82c9-b311848cb3e6" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESChangeinAccountingPrinciplesDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESChangeinAccountingPrinciplesDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESChangeinAccountingPrinciplesDetails" xlink:type="extended" id="i5435dab4cb954bb68072cbf203f196d5_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESChangeinAccountingPrinciplesDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_a4fe5704-565c-477a-a432-115cffcf833a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment_abb9b7d6-c5bb-4993-b952-361b3df0452e" xlink:href="acmr-20230630.xsd#acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_a4fe5704-565c-477a-a432-115cffcf833a" xlink:to="loc_acmr_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestIncludingPriorPeriodAdjustment_abb9b7d6-c5bb-4993-b952-361b3df0452e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_97edabb6-4e01-4033-b1cf-1a585d877aae" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_a4fe5704-565c-477a-a432-115cffcf833a" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_97edabb6-4e01-4033-b1cf-1a585d877aae" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_1a38cfe8-20a6-4127-b744-a34a694de14a" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_97edabb6-4e01-4033-b1cf-1a585d877aae" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_1a38cfe8-20a6-4127-b744-a34a694de14a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_1a38cfe8-20a6-4127-b744-a34a694de14a_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_1a38cfe8-20a6-4127-b744-a34a694de14a" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_1a38cfe8-20a6-4127-b744-a34a694de14a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_0be94ad3-e9e5-4257-a7b0-39ea01dca52a" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_1a38cfe8-20a6-4127-b744-a34a694de14a" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_0be94ad3-e9e5-4257-a7b0-39ea01dca52a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember_bedc6fa4-01db-44ca-9ea4-7b96da596261" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_0be94ad3-e9e5-4257-a7b0-39ea01dca52a" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember_bedc6fa4-01db-44ca-9ea4-7b96da596261" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_edad8ee7-f30f-4632-ab35-496e120314c4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_97edabb6-4e01-4033-b1cf-1a585d877aae" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_edad8ee7-f30f-4632-ab35-496e120314c4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_edad8ee7-f30f-4632-ab35-496e120314c4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_edad8ee7-f30f-4632-ab35-496e120314c4" xlink:to="loc_us-gaap_EquityComponentDomain_edad8ee7-f30f-4632-ab35-496e120314c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_76bd1316-e556-4069-84f5-bdf7a96fd998" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_edad8ee7-f30f-4632-ab35-496e120314c4" xlink:to="loc_us-gaap_EquityComponentDomain_76bd1316-e556-4069-84f5-bdf7a96fd998" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_9d89f89d-df97-4738-aca2-0aac1b5665d5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_76bd1316-e556-4069-84f5-bdf7a96fd998" xlink:to="loc_us-gaap_RetainedEarningsMember_9d89f89d-df97-4738-aca2-0aac1b5665d5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESCashandCashEquivalentsDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESCashandCashEquivalentsDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESCashandCashEquivalentsDetails" xlink:type="extended" id="i69d440ea7133407682b0e57c7ebf9df2_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESCashandCashEquivalentsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsLineItems_1b088601-6cf1-4da7-9e87-f79d74cba780" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_81ea3c09-f0db-4733-b22a-ba9a4ddabc9a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_1b088601-6cf1-4da7-9e87-f79d74cba780" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_81ea3c09-f0db-4733-b22a-ba9a4ddabc9a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_CashCashEquivalentsAndRestrictedCashAndTimeDeposits_762bc8e8-1521-493b-9c86-bec721fc40d7" xlink:href="acmr-20230630.xsd#acmr_CashCashEquivalentsAndRestrictedCashAndTimeDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_81ea3c09-f0db-4733-b22a-ba9a4ddabc9a" xlink:to="loc_acmr_CashCashEquivalentsAndRestrictedCashAndTimeDeposits_762bc8e8-1521-493b-9c86-bec721fc40d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositAssets_a5be85f4-c4e5-4592-a358-7d5dc223543b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_81ea3c09-f0db-4733-b22a-ba9a4ddabc9a" xlink:to="loc_us-gaap_DepositAssets_a5be85f4-c4e5-4592-a358-7d5dc223543b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToSuppliersAndEmployees_c98d00cb-7b14-4a40-830e-a9a9b56572c5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToSuppliersAndEmployees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_81ea3c09-f0db-4733-b22a-ba9a4ddabc9a" xlink:to="loc_us-gaap_PaymentsToSuppliersAndEmployees_c98d00cb-7b14-4a40-830e-a9a9b56572c5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_616fec4f-fb0d-4347-ad2b-90b83eb8f3e9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfCashAndCashEquivalentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_1b088601-6cf1-4da7-9e87-f79d74cba780" xlink:to="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_616fec4f-fb0d-4347-ad2b-90b83eb8f3e9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_bedae7e7-2bf5-46fc-973a-8c026c5c1830" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_616fec4f-fb0d-4347-ad2b-90b83eb8f3e9" xlink:to="loc_srt_StatementGeographicalAxis_bedae7e7-2bf5-46fc-973a-8c026c5c1830" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_bedae7e7-2bf5-46fc-973a-8c026c5c1830_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_bedae7e7-2bf5-46fc-973a-8c026c5c1830" xlink:to="loc_srt_SegmentGeographicalDomain_bedae7e7-2bf5-46fc-973a-8c026c5c1830_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_bedae7e7-2bf5-46fc-973a-8c026c5c1830" xlink:to="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_6bbc8005-15c3-48a6-91a0-80ec7092ff5b" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:to="loc_country_US_6bbc8005-15c3-48a6-91a0-80ec7092ff5b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_586ea7e2-8614-4af5-a627-70caeaae5af5" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:to="loc_country_CN_586ea7e2-8614-4af5-a627-70caeaae5af5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_HK_30ebdaba-041b-48b4-b14a-c658dfb45233" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_HK"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:to="loc_country_HK_30ebdaba-041b-48b4-b14a-c658dfb45233" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_KR_7e2e15e7-32e7-4fb3-ae79-9e4e6f00bb45" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_KR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:to="loc_country_KR_7e2e15e7-32e7-4fb3-ae79-9e4e6f00bb45" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_SG_11721dc1-15c7-4d68-8c1d-f05d67896900" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_SG"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c4b559b4-7d2e-4f30-b38c-31dd62c67992" xlink:to="loc_country_SG_11721dc1-15c7-4d68-8c1d-f05d67896900" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_c59f5cf0-abbb-46ba-b70c-8d22310d9440" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_616fec4f-fb0d-4347-ad2b-90b83eb8f3e9" xlink:to="loc_srt_ConsolidatedEntitiesAxis_c59f5cf0-abbb-46ba-b70c-8d22310d9440" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_c59f5cf0-abbb-46ba-b70c-8d22310d9440_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_c59f5cf0-abbb-46ba-b70c-8d22310d9440" xlink:to="loc_srt_ConsolidatedEntitiesDomain_c59f5cf0-abbb-46ba-b70c-8d22310d9440_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_1313005d-59ba-4553-b72c-ddc59a862d55" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_c59f5cf0-abbb-46ba-b70c-8d22310d9440" xlink:to="loc_srt_ConsolidatedEntitiesDomain_1313005d-59ba-4553-b72c-ddc59a862d55" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMShanghaiMember_a8dc5bf8-9452-404b-8dee-d9abcae7af5e" xlink:href="acmr-20230630.xsd#acmr_ACMShanghaiMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_1313005d-59ba-4553-b72c-ddc59a862d55" xlink:to="loc_acmr_ACMShanghaiMember_a8dc5bf8-9452-404b-8dee-d9abcae7af5e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESSummaryofFairValueDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESSummaryofFairValueDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESSummaryofFairValueDetails" xlink:type="extended" id="iae793d6af1a442b988c1a37f3d303330_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESSummaryofFairValueDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_4cb2d47d-6f46-46ca-8efc-60445bf9d8c1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0886f7a-25be-4d43-8ae7-2741912d0176" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_4cb2d47d-6f46-46ca-8efc-60445bf9d8c1" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0886f7a-25be-4d43-8ae7-2741912d0176" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_02a329de-860b-4ea3-9939-7449ac1bef7b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0886f7a-25be-4d43-8ae7-2741912d0176" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_02a329de-860b-4ea3-9939-7449ac1bef7b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecurities_13e6c105-8feb-4ecd-8282-c1a69e7b7bb5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TradingSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0886f7a-25be-4d43-8ae7-2741912d0176" xlink:to="loc_us-gaap_TradingSecurities_13e6c105-8feb-4ecd-8282-c1a69e7b7bb5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_aff7dd5c-ff11-4516-8806-d2cd1a6720e1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_e0886f7a-25be-4d43-8ae7-2741912d0176" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_aff7dd5c-ff11-4516-8806-d2cd1a6720e1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_b84a7c30-45fc-4363-99ee-02324c8d98ce" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_4cb2d47d-6f46-46ca-8efc-60445bf9d8c1" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_b84a7c30-45fc-4363-99ee-02324c8d98ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShorttermDebtFairValue_fca278fd-4266-4f8b-806d-d8e02533d588" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShorttermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_b84a7c30-45fc-4363-99ee-02324c8d98ce" xlink:to="loc_us-gaap_ShorttermDebtFairValue_fca278fd-4266-4f8b-806d-d8e02533d588" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_ee60ba61-5b7f-4d88-8f42-5664c4069f72" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_b84a7c30-45fc-4363-99ee-02324c8d98ce" xlink:to="loc_us-gaap_LongTermDebtFairValue_ee60ba61-5b7f-4d88-8f42-5664c4069f72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_c7f3e525-965e-4ebf-9521-10d43c908171" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_b84a7c30-45fc-4363-99ee-02324c8d98ce" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_c7f3e525-965e-4ebf-9521-10d43c908171" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_7bb0bfe5-bb96-4f6c-836d-1d938c349120" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_4cb2d47d-6f46-46ca-8efc-60445bf9d8c1" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_7bb0bfe5-bb96-4f6c-836d-1d938c349120" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d54915ea-6db6-43a0-b995-3ec44ee38b84" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_7bb0bfe5-bb96-4f6c-836d-1d938c349120" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d54915ea-6db6-43a0-b995-3ec44ee38b84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_d54915ea-6db6-43a0-b995-3ec44ee38b84_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d54915ea-6db6-43a0-b995-3ec44ee38b84" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_d54915ea-6db6-43a0-b995-3ec44ee38b84_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ecbc0b28-710a-424f-bddb-b24ce816d0e3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d54915ea-6db6-43a0-b995-3ec44ee38b84" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ecbc0b28-710a-424f-bddb-b24ce816d0e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_3f4cf81d-7dd5-4194-a3fc-d37a4e4ddd45" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ecbc0b28-710a-424f-bddb-b24ce816d0e3" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_3f4cf81d-7dd5-4194-a3fc-d37a4e4ddd45" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_4fb59438-2192-4b91-ba28-243ad06ad1ca" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ecbc0b28-710a-424f-bddb-b24ce816d0e3" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_4fb59438-2192-4b91-ba28-243ad06ad1ca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_319c6491-4ce1-4bfd-ab12-cce72503f2aa" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ecbc0b28-710a-424f-bddb-b24ce816d0e3" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_319c6491-4ce1-4bfd-ab12-cce72503f2aa" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESTimeDepositsDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESTimeDepositsDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESTimeDepositsDetails" xlink:type="extended" id="ief9cb03150a8406ba35f3ea868058bb8_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESTimeDepositsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_acmr_DepositsAssetsLineItems_06cb9546-8b24-4367-85a8-5e213cd1a26c" xlink:href="acmr-20230630.xsd#acmr_DepositsAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsAbstract_a28b9725-96a9-4ece-b2ed-712bd4b1c8f4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_DepositsAssetsLineItems_06cb9546-8b24-4367-85a8-5e213cd1a26c" xlink:to="loc_us-gaap_DepositsAbstract_a28b9725-96a9-4ece-b2ed-712bd4b1c8f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositAssets_79a6033d-8e44-47d8-8486-5f2110e05b08" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsAbstract_a28b9725-96a9-4ece-b2ed-712bd4b1c8f4" xlink:to="loc_us-gaap_DepositAssets_79a6033d-8e44-47d8-8486-5f2110e05b08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_TimeDepositsInterestRate_c5135956-05df-486e-8871-e51e85106ca8" xlink:href="acmr-20230630.xsd#acmr_TimeDepositsInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DepositsAbstract_a28b9725-96a9-4ece-b2ed-712bd4b1c8f4" xlink:to="loc_acmr_TimeDepositsInterestRate_c5135956-05df-486e-8871-e51e85106ca8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeDepositsWithFinancialInstitutions_dedf2aea-9014-4292-9e65-8051a5f7f806" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestIncomeDepositsWithFinancialInstitutions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_DepositsAssetsLineItems_06cb9546-8b24-4367-85a8-5e213cd1a26c" xlink:to="loc_us-gaap_InterestIncomeDepositsWithFinancialInstitutions_dedf2aea-9014-4292-9e65-8051a5f7f806" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_DepositsAssetsTable_b5c48aa2-1798-4d1c-9198-5262b34cd3c0" xlink:href="acmr-20230630.xsd#acmr_DepositsAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_acmr_DepositsAssetsLineItems_06cb9546-8b24-4367-85a8-5e213cd1a26c" xlink:to="loc_acmr_DepositsAssetsTable_b5c48aa2-1798-4d1c-9198-5262b34cd3c0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_41d136e2-09c1-46aa-b201-866eadf6a915" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_DepositsAssetsTable_b5c48aa2-1798-4d1c-9198-5262b34cd3c0" xlink:to="loc_srt_CounterpartyNameAxis_41d136e2-09c1-46aa-b201-866eadf6a915" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_41d136e2-09c1-46aa-b201-866eadf6a915_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_41d136e2-09c1-46aa-b201-866eadf6a915" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_41d136e2-09c1-46aa-b201-866eadf6a915_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_41d136e2-09c1-46aa-b201-866eadf6a915" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaMerchantBankDepositsMaturingOnJanuary292023Member_318ae9e9-7c2f-44c4-98c8-c3e40d9c41a0" xlink:href="acmr-20230630.xsd#acmr_ChinaMerchantBankDepositsMaturingOnJanuary292023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaMerchantBankDepositsMaturingOnJanuary292023Member_318ae9e9-7c2f-44c4-98c8-c3e40d9c41a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaEverbrightBankDepositMaturingOnJanuary292023Member_65c5c475-0a11-4d31-8e85-a727e49aef72" xlink:href="acmr-20230630.xsd#acmr_ChinaEverbrightBankDepositMaturingOnJanuary292023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaEverbrightBankDepositMaturingOnJanuary292023Member_65c5c475-0a11-4d31-8e85-a727e49aef72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaEverbrightBankDepositMaturingMay222023Member_102cfb4f-3ec3-4949-b492-c0cd381886af" xlink:href="acmr-20230630.xsd#acmr_ChinaEverbrightBankDepositMaturingMay222023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaEverbrightBankDepositMaturingMay222023Member_102cfb4f-3ec3-4949-b492-c0cd381886af" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaIndustrialBankDepositMaturingOnJanuary302023Member_f2e13a62-e766-4bc0-8aa5-8f4ccf615849" xlink:href="acmr-20230630.xsd#acmr_ChinaIndustrialBankDepositMaturingOnJanuary302023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaIndustrialBankDepositMaturingOnJanuary302023Member_f2e13a62-e766-4bc0-8aa5-8f4ccf615849" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaMerchantBankDepositMaturingJanuary292024Member_b1e1c6ee-d096-4041-884b-9e7997b9ae2d" xlink:href="acmr-20230630.xsd#acmr_ChinaMerchantBankDepositMaturingJanuary292024Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaMerchantBankDepositMaturingJanuary292024Member_b1e1c6ee-d096-4041-884b-9e7997b9ae2d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_BankOfNingboDepositMaturingOnFebruary172024Member_5b42c843-26d6-4405-bae4-5b2b66a69210" xlink:href="acmr-20230630.xsd#acmr_BankOfNingboDepositMaturingOnFebruary172024Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_BankOfNingboDepositMaturingOnFebruary172024Member_5b42c843-26d6-4405-bae4-5b2b66a69210" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingOctober202025Member_a04556e7-4aec-4192-9433-75f36e7165df" xlink:href="acmr-20230630.xsd#acmr_ShanghaiPudongDevelopmentBankDepositMaturingOctober202025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingOctober202025Member_a04556e7-4aec-4192-9433-75f36e7165df" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingNovember142025Member_12c05f78-3ae1-4c9c-a9eb-71df3f61bcdd" xlink:href="acmr-20230630.xsd#acmr_ShanghaiPudongDevelopmentBankDepositMaturingNovember142025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingNovember142025Member_12c05f78-3ae1-4c9c-a9eb-71df3f61bcdd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember82025Member_3d7e617e-5f1c-4316-b751-9a5da3dee0b8" xlink:href="acmr-20230630.xsd#acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember82025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember82025Member_3d7e617e-5f1c-4316-b751-9a5da3dee0b8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember152025Member_20b70100-802e-4a8f-b167-73aa0729162a" xlink:href="acmr-20230630.xsd#acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember152025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember152025Member_20b70100-802e-4a8f-b167-73aa0729162a" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember302025Member_dac472d1-4d1e-4ed9-aac8-8082d64211a0" xlink:href="acmr-20230630.xsd#acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember302025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ShanghaiPudongDevelopmentBankDepositMaturingDecember302025Member_dac472d1-4d1e-4ed9-aac8-8082d64211a0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaEverbrightBankDepositMaturingJuly42023Member_9cc454bc-0935-47d8-b1f1-44127f1f83af" xlink:href="acmr-20230630.xsd#acmr_ChinaEverbrightBankDepositMaturingJuly42023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaEverbrightBankDepositMaturingJuly42023Member_9cc454bc-0935-47d8-b1f1-44127f1f83af" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaEverbrightBankDepositMaturingNovember222023Member_61767def-113c-4af2-b0c6-80e4e70871c8" xlink:href="acmr-20230630.xsd#acmr_ChinaEverbrightBankDepositMaturingNovember222023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaEverbrightBankDepositMaturingNovember222023Member_61767def-113c-4af2-b0c6-80e4e70871c8" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaMerchantBankDepositMaturingJanuary302026Member_44199ada-1762-4c40-981d-6363518e51bb" xlink:href="acmr-20230630.xsd#acmr_ChinaMerchantBankDepositMaturingJanuary302026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_49eddc64-bd03-49f8-9294-d62a883fe4c3" xlink:to="loc_acmr_ChinaMerchantBankDepositMaturingJanuary302026Member_44199ada-1762-4c40-981d-6363518e51bb" xlink:type="arc" order="13"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESConcentrationofCreditRiskDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESConcentrationofCreditRiskDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESConcentrationofCreditRiskDetails" xlink:type="extended" id="i725161a100f34cf886c8822f6aabadfe_SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESConcentrationofCreditRiskDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_af4cdf43-0386-4832-b9bd-141c88ecfb73" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ConcentrationOfCreditRiskAbstract_20a05f5e-1073-459d-b209-505ca3e02843" xlink:href="acmr-20230630.xsd#acmr_ConcentrationOfCreditRiskAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_af4cdf43-0386-4832-b9bd-141c88ecfb73" xlink:to="loc_acmr_ConcentrationOfCreditRiskAbstract_20a05f5e-1073-459d-b209-505ca3e02843" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NumberOfMajorCustomers_d37d935e-eb26-49f4-bae7-26000f0777be" xlink:href="acmr-20230630.xsd#acmr_NumberOfMajorCustomers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_ConcentrationOfCreditRiskAbstract_20a05f5e-1073-459d-b209-505ca3e02843" xlink:to="loc_acmr_NumberOfMajorCustomers_d37d935e-eb26-49f4-bae7-26000f0777be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_af11a875-2305-4d7f-98e0-e5d780d3a6cf" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_ConcentrationOfCreditRiskAbstract_20a05f5e-1073-459d-b209-505ca3e02843" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_af11a875-2305-4d7f-98e0-e5d780d3a6cf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTable_f0b4c8f8-d3f6-4177-9a62-711b4ed0e16d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_af4cdf43-0386-4832-b9bd-141c88ecfb73" xlink:to="loc_us-gaap_ConcentrationRiskTable_f0b4c8f8-d3f6-4177-9a62-711b4ed0e16d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_8b435aeb-e4e8-4258-8652-13db2fc53807" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_f0b4c8f8-d3f6-4177-9a62-711b4ed0e16d" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_8b435aeb-e4e8-4258-8652-13db2fc53807" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8b435aeb-e4e8-4258-8652-13db2fc53807_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_8b435aeb-e4e8-4258-8652-13db2fc53807" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_8b435aeb-e4e8-4258-8652-13db2fc53807_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_50f93ae8-e1c2-414d-87f3-d9741f2a493f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_8b435aeb-e4e8-4258-8652-13db2fc53807" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_50f93ae8-e1c2-414d-87f3-d9741f2a493f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_32299e0d-ab44-458d-8ad7-71881a74d959" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_50f93ae8-e1c2-414d-87f3-d9741f2a493f" xlink:to="loc_us-gaap_SalesRevenueNetMember_32299e0d-ab44-458d-8ad7-71881a74d959" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableMember_cf4ae5db-5160-4526-b3e1-2ede53d95251" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountsReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_50f93ae8-e1c2-414d-87f3-d9741f2a493f" xlink:to="loc_us-gaap_AccountsReceivableMember_cf4ae5db-5160-4526-b3e1-2ede53d95251" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_466a71c3-295d-4fea-8242-b61523dc0775" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_f0b4c8f8-d3f6-4177-9a62-711b4ed0e16d" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_466a71c3-295d-4fea-8242-b61523dc0775" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_466a71c3-295d-4fea-8242-b61523dc0775_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_466a71c3-295d-4fea-8242-b61523dc0775" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_466a71c3-295d-4fea-8242-b61523dc0775_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_b72bce30-b9fa-410c-9681-315a1b942e47" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_466a71c3-295d-4fea-8242-b61523dc0775" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_b72bce30-b9fa-410c-9681-315a1b942e47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_23f8f085-27c6-4e13-bded-ca0d958eed67" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_b72bce30-b9fa-410c-9681-315a1b942e47" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_23f8f085-27c6-4e13-bded-ca0d958eed67" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_481d52b2-fda4-40d5-aa3c-1ec634ef509d" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_f0b4c8f8-d3f6-4177-9a62-711b4ed0e16d" xlink:to="loc_srt_MajorCustomersAxis_481d52b2-fda4-40d5-aa3c-1ec634ef509d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_481d52b2-fda4-40d5-aa3c-1ec634ef509d_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_481d52b2-fda4-40d5-aa3c-1ec634ef509d" xlink:to="loc_srt_NameOfMajorCustomerDomain_481d52b2-fda4-40d5-aa3c-1ec634ef509d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_dd21db14-ce08-43c5-8452-792b5cd79c94" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_481d52b2-fda4-40d5-aa3c-1ec634ef509d" xlink:to="loc_srt_NameOfMajorCustomerDomain_dd21db14-ce08-43c5-8452-792b5cd79c94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ThreeCustomersMember_c8e1dbdd-f97d-4d1c-ba07-629e9d1f57d7" xlink:href="acmr-20230630.xsd#acmr_ThreeCustomersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_dd21db14-ce08-43c5-8452-792b5cd79c94" xlink:to="loc_acmr_ThreeCustomersMember_c8e1dbdd-f97d-4d1c-ba07-629e9d1f57d7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_FourCustomersMember_7efb6566-ca56-456d-a3ba-cc875b9ca456" xlink:href="acmr-20230630.xsd#acmr_FourCustomersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_dd21db14-ce08-43c5-8452-792b5cd79c94" xlink:to="loc_acmr_FourCustomersMember_7efb6566-ca56-456d-a3ba-cc875b9ca456" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_OneCustomerMember_49f37f3d-77f2-4f24-8853-51d0844aa768" xlink:href="acmr-20230630.xsd#acmr_OneCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_dd21db14-ce08-43c5-8452-792b5cd79c94" xlink:to="loc_acmr_OneCustomerMember_49f37f3d-77f2-4f24-8853-51d0844aa768" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_TwoCustomersMember_8d179f4c-7071-4231-a056-01a71b7f7dec" xlink:href="acmr-20230630.xsd#acmr_TwoCustomersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_dd21db14-ce08-43c5-8452-792b5cd79c94" xlink:to="loc_acmr_TwoCustomersMember_8d179f4c-7071-4231-a056-01a71b7f7dec" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/REVENUEFROMCONTRACTSWITHCUSTOMERSDisaggregatedRevenueDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#REVENUEFROMCONTRACTSWITHCUSTOMERSDisaggregatedRevenueDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/REVENUEFROMCONTRACTSWITHCUSTOMERSDisaggregatedRevenueDetails" xlink:type="extended" id="if3b82aae5379412785237cb56a2635bc_REVENUEFROMCONTRACTSWITHCUSTOMERSDisaggregatedRevenueDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_d9b319e8-6ddc-4783-a3a6-9a239d8bb792" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_DisaggregatedRevenueInformationAbstract_f4db2f71-599b-448a-9c5d-8df7c70bcf26" xlink:href="acmr-20230630.xsd#acmr_DisaggregatedRevenueInformationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_d9b319e8-6ddc-4783-a3a6-9a239d8bb792" xlink:to="loc_acmr_DisaggregatedRevenueInformationAbstract_f4db2f71-599b-448a-9c5d-8df7c70bcf26" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_66780dc9-e433-47c7-a56c-09f56ec069cc" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_DisaggregatedRevenueInformationAbstract_f4db2f71-599b-448a-9c5d-8df7c70bcf26" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_66780dc9-e433-47c7-a56c-09f56ec069cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_a8c56b0f-accb-417f-85e9-db75391c3871" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_d9b319e8-6ddc-4783-a3a6-9a239d8bb792" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_a8c56b0f-accb-417f-85e9-db75391c3871" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_cd36e6c1-5889-4c7e-89c7-e86c9ca1ec6c" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a8c56b0f-accb-417f-85e9-db75391c3871" xlink:to="loc_srt_ProductOrServiceAxis_cd36e6c1-5889-4c7e-89c7-e86c9ca1ec6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_cd36e6c1-5889-4c7e-89c7-e86c9ca1ec6c_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_cd36e6c1-5889-4c7e-89c7-e86c9ca1ec6c" xlink:to="loc_srt_ProductsAndServicesDomain_cd36e6c1-5889-4c7e-89c7-e86c9ca1ec6c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_cd36e6c1-5889-4c7e-89c7-e86c9ca1ec6c" xlink:to="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_TotalSingleWaferAndSemiCriticalCleaningEquipmentMember_7c0b3ce5-13ab-4a06-8cd7-9883b2498359" xlink:href="acmr-20230630.xsd#acmr_TotalSingleWaferAndSemiCriticalCleaningEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:to="loc_acmr_TotalSingleWaferAndSemiCriticalCleaningEquipmentMember_7c0b3ce5-13ab-4a06-8cd7-9883b2498359" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ECPFrontEndAndPackagingFurnaceAndOtherTechnologiesMember_346c58fa-827f-4d0e-9e9e-96250ef63006" xlink:href="acmr-20230630.xsd#acmr_ECPFrontEndAndPackagingFurnaceAndOtherTechnologiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:to="loc_acmr_ECPFrontEndAndPackagingFurnaceAndOtherTechnologiesMember_346c58fa-827f-4d0e-9e9e-96250ef63006" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_AdvancedPackagingExcludeECPServicesSparesMember_876336e5-1a69-4f53-89ea-023c0b674472" xlink:href="acmr-20230630.xsd#acmr_AdvancedPackagingExcludeECPServicesSparesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:to="loc_acmr_AdvancedPackagingExcludeECPServicesSparesMember_876336e5-1a69-4f53-89ea-023c0b674472" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_WetCleaningAndOtherFrontEndProcessingToolsMember_1212a72e-2098-495e-9443-8c11e026e1ab" xlink:href="acmr-20230630.xsd#acmr_WetCleaningAndOtherFrontEndProcessingToolsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:to="loc_acmr_WetCleaningAndOtherFrontEndProcessingToolsMember_1212a72e-2098-495e-9443-8c11e026e1ab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_AdvancedPackagingOtherProcessingServicesAndSparesMember_0913b26b-5820-4f6d-afa1-23191f416e3c" xlink:href="acmr-20230630.xsd#acmr_AdvancedPackagingOtherProcessingServicesAndSparesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_5aa35924-8b4e-4992-bc2b-c92035b6de82" xlink:to="loc_acmr_AdvancedPackagingOtherProcessingServicesAndSparesMember_0913b26b-5820-4f6d-afa1-23191f416e3c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_ae32ae6d-06e9-4730-891e-34c79209ac36" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a8c56b0f-accb-417f-85e9-db75391c3871" xlink:to="loc_srt_StatementGeographicalAxis_ae32ae6d-06e9-4730-891e-34c79209ac36" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_ae32ae6d-06e9-4730-891e-34c79209ac36_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_ae32ae6d-06e9-4730-891e-34c79209ac36" xlink:to="loc_srt_SegmentGeographicalDomain_ae32ae6d-06e9-4730-891e-34c79209ac36_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_c2ca6be1-a80b-4d11-9e8a-40880b7f2c0d" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_ae32ae6d-06e9-4730-891e-34c79209ac36" xlink:to="loc_srt_SegmentGeographicalDomain_c2ca6be1-a80b-4d11-9e8a-40880b7f2c0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_9bdeaca4-3062-4b59-9d58-463924c1ac10" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c2ca6be1-a80b-4d11-9e8a-40880b7f2c0d" xlink:to="loc_country_CN_9bdeaca4-3062-4b59-9d58-463924c1ac10" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_OherRegionsMember_75ea6822-9d48-4874-b3ab-19e7de7464b8" xlink:href="acmr-20230630.xsd#acmr_OherRegionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_c2ca6be1-a80b-4d11-9e8a-40880b7f2c0d" xlink:to="loc_acmr_OherRegionsMember_75ea6822-9d48-4874-b3ab-19e7de7464b8" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/REVENUEFROMCONTRACTSWITHCUSTOMERSNarrativeDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#REVENUEFROMCONTRACTSWITHCUSTOMERSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/REVENUEFROMCONTRACTSWITHCUSTOMERSNarrativeDetails" xlink:type="extended" id="ie5b22e7b150d4eb39ccbc718d3080e2d_REVENUEFROMCONTRACTSWITHCUSTOMERSNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_2b08b777-c714-451c-bb0c-f3e849e1ff72" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_d70f6052-f008-4b8c-877b-b61702479d8e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_2b08b777-c714-451c-bb0c-f3e849e1ff72" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_d70f6052-f008-4b8c-877b-b61702479d8e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_9011b7fd-a53f-450d-ad14-3533a5ac3e22" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_2b08b777-c714-451c-bb0c-f3e849e1ff72" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_9011b7fd-a53f-450d-ad14-3533a5ac3e22" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryAxis_c2233866-f8f8-4d28-96b2-bf6f740ad5c5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PublicUtilitiesInventoryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_9011b7fd-a53f-450d-ad14-3533a5ac3e22" xlink:to="loc_us-gaap_PublicUtilitiesInventoryAxis_c2233866-f8f8-4d28-96b2-bf6f740ad5c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_c2233866-f8f8-4d28-96b2-bf6f740ad5c5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PublicUtilitiesInventoryTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PublicUtilitiesInventoryAxis_c2233866-f8f8-4d28-96b2-bf6f740ad5c5" xlink:to="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_c2233866-f8f8-4d28-96b2-bf6f740ad5c5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_778a3569-f71c-40a1-8eec-37f88b1c5ef6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PublicUtilitiesInventoryTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PublicUtilitiesInventoryAxis_c2233866-f8f8-4d28-96b2-bf6f740ad5c5" xlink:to="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_778a3569-f71c-40a1-8eec-37f88b1c5ef6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_FirstToolsMember_8fd51a12-995a-48b7-a9fe-63aae44ad2f3" xlink:href="acmr-20230630.xsd#acmr_FirstToolsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_778a3569-f71c-40a1-8eec-37f88b1c5ef6" xlink:to="loc_acmr_FirstToolsMember_8fd51a12-995a-48b7-a9fe-63aae44ad2f3" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/ACCOUNTSRECEIVABLESummaryofAllowanceForDoubtfulAccountsDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#ACCOUNTSRECEIVABLESummaryofAllowanceForDoubtfulAccountsDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/ACCOUNTSRECEIVABLESummaryofAllowanceForDoubtfulAccountsDetails" xlink:type="extended" id="ibf6dbf4204cb49b98ae2c27314ea7d79_ACCOUNTSRECEIVABLESummaryofAllowanceForDoubtfulAccountsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_d153c050-afda-456c-891a-d79a5b70596e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_9f6f5d18-00c2-4064-8665-4f5e341271c1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_d153c050-afda-456c-891a-d79a5b70596e" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_9f6f5d18-00c2-4064-8665-4f5e341271c1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_302b9863-ba8d-4278-8cd8-564f4b0f49c1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_9f6f5d18-00c2-4064-8665-4f5e341271c1" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_302b9863-ba8d-4278-8cd8-564f4b0f49c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_AccountsReceivableCreditLossExpenseReversalIncludingForeignCurrencyExchangeRate_b8574365-b624-42fb-9411-7eca15581352" xlink:href="acmr-20230630.xsd#acmr_AccountsReceivableCreditLossExpenseReversalIncludingForeignCurrencyExchangeRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_9f6f5d18-00c2-4064-8665-4f5e341271c1" xlink:to="loc_acmr_AccountsReceivableCreditLossExpenseReversalIncludingForeignCurrencyExchangeRate_b8574365-b624-42fb-9411-7eca15581352" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_be1d8287-deb7-4e65-9538-f5092acccf13" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_987991ed-d609-47fd-ada6-61e1d52ec8f0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_d153c050-afda-456c-891a-d79a5b70596e" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_987991ed-d609-47fd-ada6-61e1d52ec8f0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_7f66aee4-8c70-4830-8faa-20330393c10c" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_987991ed-d609-47fd-ada6-61e1d52ec8f0" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_7f66aee4-8c70-4830-8faa-20330393c10c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_7f66aee4-8c70-4830-8faa-20330393c10c_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_7f66aee4-8c70-4830-8faa-20330393c10c" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_7f66aee4-8c70-4830-8faa-20330393c10c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_a7b00013-6877-48bb-bf69-3294e644e68b" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis_7f66aee4-8c70-4830-8faa-20330393c10c" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_a7b00013-6877-48bb-bf69-3294e644e68b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember_b6fa6724-ac9a-49af-9d7c-b671d0ffb599" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionDomain_a7b00013-6877-48bb-bf69-3294e644e68b" xlink:to="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember_b6fa6724-ac9a-49af-9d7c-b671d0ffb599" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/INVENTORIESDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#INVENTORIESDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/INVENTORIESDetails" xlink:type="extended" id="i9698f316904b4948aa0e7702d25ff299_INVENTORIESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryLineItems_a98e679f-7b71-4b77-82e6-4c2b1a792e63" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryLineItems_a98e679f-7b71-4b77-82e6-4c2b1a792e63" xlink:to="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterials_955fad02-1a5c-4ad5-8be2-3dee2de1cc01" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryRawMaterials"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_us-gaap_InventoryRawMaterials_955fad02-1a5c-4ad5-8be2-3dee2de1cc01" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWorkInProcess_2f08003e-aa6a-4a7a-97cc-56d34e5512cd" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryWorkInProcess"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_us-gaap_InventoryWorkInProcess_2f08003e-aa6a-4a7a-97cc-56d34e5512cd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryFinishedGoods_3f3f6bd0-a386-4b36-9d10-7ded1ffbdcc3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryFinishedGoods"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_us-gaap_InventoryFinishedGoods_3f3f6bd0-a386-4b36-9d10-7ded1ffbdcc3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryGross_0121a7e8-e895-4754-9084-d9c52465e60e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_us-gaap_InventoryGross_0121a7e8-e895-4754-9084-d9c52465e60e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_IncreaseDecreaseInRawMaterialsAndWorkInProcessInventory_389ccd3f-7f36-41e8-8aa6-ea964662914d" xlink:href="acmr-20230630.xsd#acmr_IncreaseDecreaseInRawMaterialsAndWorkInProcessInventory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_acmr_IncreaseDecreaseInRawMaterialsAndWorkInProcessInventory_389ccd3f-7f36-41e8-8aa6-ea964662914d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_IncreaseDecreaseInFinishedGoodsInventory_19559059-65b2-46b4-a42a-7287e97462a5" xlink:href="acmr-20230630.xsd#acmr_IncreaseDecreaseInFinishedGoodsInventory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_acmr_IncreaseDecreaseInFinishedGoodsInventory_19559059-65b2-46b4-a42a-7287e97462a5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_InventoryImpairmentPeriod_ff277062-de8a-45a3-9bb4-5269baf3f0d8" xlink:href="acmr-20230630.xsd#acmr_InventoryImpairmentPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_acmr_InventoryImpairmentPeriod_ff277062-de8a-45a3-9bb4-5269baf3f0d8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWriteDown_a9732a12-b190-4b9c-9319-6014f8a8ff4a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryWriteDown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_dd75d65a-5b30-4528-8dc7-55c345967822" xlink:to="loc_us-gaap_InventoryWriteDown_a9732a12-b190-4b9c-9319-6014f8a8ff4a" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryCurrentTable_84f2c40f-1ca3-4f7f-a274-69afa369d63f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InventoryCurrentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_InventoryLineItems_a98e679f-7b71-4b77-82e6-4c2b1a792e63" xlink:to="loc_us-gaap_InventoryCurrentTable_84f2c40f-1ca3-4f7f-a274-69afa369d63f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryAxis_00ac4851-302f-4e6a-8780-2493257239af" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PublicUtilitiesInventoryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_InventoryCurrentTable_84f2c40f-1ca3-4f7f-a274-69afa369d63f" xlink:to="loc_us-gaap_PublicUtilitiesInventoryAxis_00ac4851-302f-4e6a-8780-2493257239af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_00ac4851-302f-4e6a-8780-2493257239af_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PublicUtilitiesInventoryTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PublicUtilitiesInventoryAxis_00ac4851-302f-4e6a-8780-2493257239af" xlink:to="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_00ac4851-302f-4e6a-8780-2493257239af_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_170ceae1-82c4-4ad7-9a1b-d44392a64b61" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PublicUtilitiesInventoryTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PublicUtilitiesInventoryAxis_00ac4851-302f-4e6a-8780-2493257239af" xlink:to="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_170ceae1-82c4-4ad7-9a1b-d44392a64b61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_FirstToolsMember_23ee4515-a720-492d-83aa-93ce644f1715" xlink:href="acmr-20230630.xsd#acmr_FirstToolsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PublicUtilitiesInventoryTypeDomain_170ceae1-82c4-4ad7-9a1b-d44392a64b61" xlink:to="loc_acmr_FirstToolsMember_23ee4515-a720-492d-83aa-93ce644f1715" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/PROPERTYPLANTANDEQUIPMENTNETDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#PROPERTYPLANTANDEQUIPMENTNETDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/PROPERTYPLANTANDEQUIPMENTNETDetails" xlink:type="extended" id="iced9fe38dd244697a62477ecb8d64a5c_PROPERTYPLANTANDEQUIPMENTNETDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_18a21e1a-46b9-4205-8d9f-39d815ad4505" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_18a21e1a-46b9-4205-8d9f-39d815ad4505" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_a04240e0-04db-407c-96f3-21909b9d3d87" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_a04240e0-04db-407c-96f3-21909b9d3d87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_6eda2a6a-6aa6-482a-9c0c-934b8c35c210" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_6eda2a6a-6aa6-482a-9c0c-934b8c35c210" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionInProgressGross_6ee79357-2a4c-4a5e-a628-e8674ec9cb55" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConstructionInProgressGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:to="loc_us-gaap_ConstructionInProgressGross_6ee79357-2a4c-4a5e-a628-e8674ec9cb55" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_1675e8f4-0c42-48bb-b888-7700919c4ddf" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_1675e8f4-0c42-48bb-b888-7700919c4ddf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_8f325756-ccc5-4bf5-b38d-a2848e3219eb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_8f325756-ccc5-4bf5-b38d-a2848e3219eb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_9c3e4125-6c4f-41b5-9bd5-452c3887994f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetByTypeAbstract_499cba79-42d4-4665-99b1-a166b18e0065" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_9c3e4125-6c4f-41b5-9bd5-452c3887994f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_d391c614-526f-4bc4-8a84-3a87e30e7c64" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_18a21e1a-46b9-4205-8d9f-39d815ad4505" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_d391c614-526f-4bc4-8a84-3a87e30e7c64" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1825fc2f-81ed-4233-9d90-6d452bc3e841" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_d391c614-526f-4bc4-8a84-3a87e30e7c64" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1825fc2f-81ed-4233-9d90-6d452bc3e841" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_1825fc2f-81ed-4233-9d90-6d452bc3e841_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1825fc2f-81ed-4233-9d90-6d452bc3e841" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_1825fc2f-81ed-4233-9d90-6d452bc3e841_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_1825fc2f-81ed-4233-9d90-6d452bc3e841" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_BuildingsAndPlantsMember_724067b6-f7d8-477e-91e0-9ec42ff7944c" xlink:href="acmr-20230630.xsd#acmr_BuildingsAndPlantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:to="loc_acmr_BuildingsAndPlantsMember_724067b6-f7d8-477e-91e0-9ec42ff7944c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentMember_669ca3f9-f4a0-400d-af4c-14c989e3fe1e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:to="loc_us-gaap_EquipmentMember_669ca3f9-f4a0-400d-af4c-14c989e3fe1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OfficeEquipmentMember_4daee2f6-e6e4-4af3-a2eb-88b93b7e778b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OfficeEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:to="loc_us-gaap_OfficeEquipmentMember_4daee2f6-e6e4-4af3-a2eb-88b93b7e778b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransportationEquipmentMember_dc8f74e0-156d-403f-9c83-07a143da23db" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransportationEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:to="loc_us-gaap_TransportationEquipmentMember_dc8f74e0-156d-403f-9c83-07a143da23db" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_d492ede2-3c2d-4083-9c2c-7cfdbbffc067" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LeaseholdImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_f55eb427-d82e-4404-86db-cb9b2d5e1c66" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_d492ede2-3c2d-4083-9c2c-7cfdbbffc067" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_1f7a8b6f-be0c-4c57-9ebc-470ea5c548b2" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_d391c614-526f-4bc4-8a84-3a87e30e7c64" xlink:to="loc_srt_ConsolidatedEntitiesAxis_1f7a8b6f-be0c-4c57-9ebc-470ea5c548b2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_1f7a8b6f-be0c-4c57-9ebc-470ea5c548b2_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_1f7a8b6f-be0c-4c57-9ebc-470ea5c548b2" xlink:to="loc_srt_ConsolidatedEntitiesDomain_1f7a8b6f-be0c-4c57-9ebc-470ea5c548b2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_001130ee-51ed-41f5-8410-22319741464c" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_1f7a8b6f-be0c-4c57-9ebc-470ea5c548b2" xlink:to="loc_srt_ConsolidatedEntitiesDomain_001130ee-51ed-41f5-8410-22319741464c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMLingangMember_2b648298-27cc-41a2-8051-abb80934ba11" xlink:href="acmr-20230630.xsd#acmr_ACMLingangMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_001130ee-51ed-41f5-8410-22319741464c" xlink:to="loc_acmr_ACMLingangMember_2b648298-27cc-41a2-8051-abb80934ba11" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/LANDUSERIGHTNETNarrativeDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#LANDUSERIGHTNETNarrativeDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/LANDUSERIGHTNETNarrativeDetails" xlink:type="extended" id="iebde23eb79b64136a57cc0909482222f_LANDUSERIGHTNETNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_db9a3676-7c12-4f50-95d0-3f916fe49214" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_RightToUseLandLeaseTerm_e43e4c1f-aaa4-4aef-8239-5cbded468815" xlink:href="acmr-20230630.xsd#acmr_RightToUseLandLeaseTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_db9a3676-7c12-4f50-95d0-3f916fe49214" xlink:to="loc_acmr_RightToUseLandLeaseTerm_e43e4c1f-aaa4-4aef-8239-5cbded468815" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_AreaOfSquareFootForDevelopmentAndProductionCenter_c162acea-f50a-472e-86dc-98de5b22cca9" xlink:href="acmr-20230630.xsd#acmr_AreaOfSquareFootForDevelopmentAndProductionCenter"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_db9a3676-7c12-4f50-95d0-3f916fe49214" xlink:to="loc_acmr_AreaOfSquareFootForDevelopmentAndProductionCenter_c162acea-f50a-472e-86dc-98de5b22cca9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_AmortizationOfGroundLease_2fce0306-bdf2-4c0f-830e-92b4c7f55893" xlink:href="acmr-20230630.xsd#acmr_AmortizationOfGroundLease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_db9a3676-7c12-4f50-95d0-3f916fe49214" xlink:to="loc_acmr_AmortizationOfGroundLease_2fce0306-bdf2-4c0f-830e-92b4c7f55893" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_f8c40f95-f6ef-48ab-bdb3-f280d359db18" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems_db9a3676-7c12-4f50-95d0-3f916fe49214" xlink:to="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_f8c40f95-f6ef-48ab-bdb3-f280d359db18" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_0afe763b-5c3c-4367-bedd-d410d301de10" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable_f8c40f95-f6ef-48ab-bdb3-f280d359db18" xlink:to="loc_srt_ConsolidatedEntitiesAxis_0afe763b-5c3c-4367-bedd-d410d301de10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_0afe763b-5c3c-4367-bedd-d410d301de10_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_0afe763b-5c3c-4367-bedd-d410d301de10" xlink:to="loc_srt_ConsolidatedEntitiesDomain_0afe763b-5c3c-4367-bedd-d410d301de10_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_eb253a4f-197d-465f-aa3d-52a48dc26cbf" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_0afe763b-5c3c-4367-bedd-d410d301de10" xlink:to="loc_srt_ConsolidatedEntitiesDomain_eb253a4f-197d-465f-aa3d-52a48dc26cbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengweiResearchShanghaiIncMember_90483aae-4449-46a3-9269-364c73d39166" xlink:href="acmr-20230630.xsd#acmr_ShengweiResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_eb253a4f-197d-465f-aa3d-52a48dc26cbf" xlink:to="loc_acmr_ShengweiResearchShanghaiIncMember_90483aae-4449-46a3-9269-364c73d39166" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/OTHERLONGTERMASSETSNarrativeDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#OTHERLONGTERMASSETSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/OTHERLONGTERMASSETSNarrativeDetails" xlink:type="extended" id="i7198565b954b428085a85c4411d94132_OTHERLONGTERMASSETSNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_b73fa459-bb56-4df3-aaaa-16a99d68048a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_1672ab5f-7cbf-42d7-8a10-0d523990a8a3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_b73fa459-bb56-4df3-aaaa-16a99d68048a" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_1672ab5f-7cbf-42d7-8a10-0d523990a8a3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_7215cffa-6891-47e1-9228-16c4f9a9a6c5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_b73fa459-bb56-4df3-aaaa-16a99d68048a" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_7215cffa-6891-47e1-9228-16c4f9a9a6c5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_f8f0ff75-e78d-4b54-a148-db385705c1c5" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_7215cffa-6891-47e1-9228-16c4f9a9a6c5" xlink:to="loc_srt_ConsolidatedEntitiesAxis_f8f0ff75-e78d-4b54-a148-db385705c1c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_f8f0ff75-e78d-4b54-a148-db385705c1c5_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_f8f0ff75-e78d-4b54-a148-db385705c1c5" xlink:to="loc_srt_ConsolidatedEntitiesDomain_f8f0ff75-e78d-4b54-a148-db385705c1c5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_7bcaebc5-52d0-42ee-ba38-80af9127f06c" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_f8f0ff75-e78d-4b54-a148-db385705c1c5" xlink:to="loc_srt_ConsolidatedEntitiesDomain_7bcaebc5-52d0-42ee-ba38-80af9127f06c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengweiResearchShanghaiIncMember_9ece4d0c-4520-45eb-808a-8de3d021b825" xlink:href="acmr-20230630.xsd#acmr_ShengweiResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_7bcaebc5-52d0-42ee-ba38-80af9127f06c" xlink:to="loc_acmr_ShengweiResearchShanghaiIncMember_9ece4d0c-4520-45eb-808a-8de3d021b825" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_7775d3cb-a0fb-4d92-a923-d0dfb1590ec5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_7215cffa-6891-47e1-9228-16c4f9a9a6c5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_7775d3cb-a0fb-4d92-a923-d0dfb1590ec5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_7775d3cb-a0fb-4d92-a923-d0dfb1590ec5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_7775d3cb-a0fb-4d92-a923-d0dfb1590ec5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_7775d3cb-a0fb-4d92-a923-d0dfb1590ec5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_58d18eee-1de1-4e04-a585-a6226546d4d1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_7775d3cb-a0fb-4d92-a923-d0dfb1590ec5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_58d18eee-1de1-4e04-a585-a6226546d4d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_BuildingsAndPlantsMember_16d9db2f-b98b-4be3-8a94-0cbce5bf3fe6" xlink:href="acmr-20230630.xsd#acmr_BuildingsAndPlantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_58d18eee-1de1-4e04-a585-a6226546d4d1" xlink:to="loc_acmr_BuildingsAndPlantsMember_16d9db2f-b98b-4be3-8a94-0cbce5bf3fe6" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SHORTTERMBORROWINGSDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SHORTTERMBORROWINGSDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SHORTTERMBORROWINGSDetails" xlink:type="extended" id="i8f3fe1d89d644c93b4caed8849f36ca5_SHORTTERMBORROWINGSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtLineItems_045001b1-ae0a-4904-a46a-f8498707fb40" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermDebtLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermBorrowingsAbstract_050bd9eb-1547-4d53-937a-418a60c59755" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermBorrowingsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermDebtLineItems_045001b1-ae0a-4904-a46a-f8498707fb40" xlink:to="loc_us-gaap_ShortTermBorrowingsAbstract_050bd9eb-1547-4d53-937a-418a60c59755" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_686a2bff-c663-4431-88c2-28f1afa72a1e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermBorrowingsAbstract_050bd9eb-1547-4d53-937a-418a60c59755" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_686a2bff-c663-4431-88c2-28f1afa72a1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermBorrowings_68d2dffc-49c1-4f2a-a16e-057466cefcec" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermBorrowingsAbstract_050bd9eb-1547-4d53-937a-418a60c59755" xlink:to="loc_us-gaap_ShortTermBorrowings_68d2dffc-49c1-4f2a-a16e-057466cefcec" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_91a4dd5f-c178-4d06-a924-2abe1a333021" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermBorrowingsAbstract_050bd9eb-1547-4d53-937a-418a60c59755" xlink:to="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_91a4dd5f-c178-4d06-a924-2abe1a333021" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseShortTermBorrowings_babe4758-25a1-4056-9bd1-4fb6df2e35cd" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseShortTermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermDebtLineItems_045001b1-ae0a-4904-a46a-f8498707fb40" xlink:to="loc_us-gaap_InterestExpenseShortTermBorrowings_babe4758-25a1-4056-9bd1-4fb6df2e35cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShortTermDebtTable_aa31160f-06a3-4bd6-92b8-b5edf8a85582" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfShortTermDebtTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShortTermDebtLineItems_045001b1-ae0a-4904-a46a-f8498707fb40" xlink:to="loc_us-gaap_ScheduleOfShortTermDebtTable_aa31160f-06a3-4bd6-92b8-b5edf8a85582" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_dc0254d5-4820-44b8-9411-e19d81890c22" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTable_aa31160f-06a3-4bd6-92b8-b5edf8a85582" xlink:to="loc_us-gaap_DebtInstrumentAxis_dc0254d5-4820-44b8-9411-e19d81890c22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_dc0254d5-4820-44b8-9411-e19d81890c22_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_dc0254d5-4820-44b8-9411-e19d81890c22" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_dc0254d5-4820-44b8-9411-e19d81890c22_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_d8abe0b1-fc91-4fd5-ab00-be66ed4d2dac" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_dc0254d5-4820-44b8-9411-e19d81890c22" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_d8abe0b1-fc91-4fd5-ab00-be66ed4d2dac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditUpToRMB150000FromChinaEverbrightBankMember_5843a712-b738-4f00-9f1d-67f7b4aa648b" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditUpToRMB150000FromChinaEverbrightBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_d8abe0b1-fc91-4fd5-ab00-be66ed4d2dac" xlink:to="loc_acmr_LineOfCreditUpToRMB150000FromChinaEverbrightBankMember_5843a712-b738-4f00-9f1d-67f7b4aa648b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust172023WithAnAnnualInterestRateOf340Member_0c24eafe-ddd4-4080-8211-e4306b66c087" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust172023WithAnAnnualInterestRateOf340Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB150000FromChinaEverbrightBankMember_5843a712-b738-4f00-9f1d-67f7b4aa648b" xlink:to="loc_acmr_LineOfCreditDueOnAugust172023WithAnAnnualInterestRateOf340Member_0c24eafe-ddd4-4080-8211-e4306b66c087" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnSeptember12023WithAnAnnualInterestRateOf360Member_1631cf79-ad99-48e8-baec-10536c77cb13" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnSeptember12023WithAnAnnualInterestRateOf360Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB150000FromChinaEverbrightBankMember_5843a712-b738-4f00-9f1d-67f7b4aa648b" xlink:to="loc_acmr_LineOfCreditDueOnSeptember12023WithAnAnnualInterestRateOf360Member_1631cf79-ad99-48e8-baec-10536c77cb13" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnDecember162023WithAnAnnualInterestRateOf300Member_4bda52c2-a757-42bf-bb3a-c019393ac8c7" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnDecember162023WithAnAnnualInterestRateOf300Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB150000FromChinaEverbrightBankMember_5843a712-b738-4f00-9f1d-67f7b4aa648b" xlink:to="loc_acmr_LineOfCreditDueOnDecember162023WithAnAnnualInterestRateOf300Member_4bda52c2-a757-42bf-bb3a-c019393ac8c7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditUpToRMB100000FromBankOfCommunicationsMember_6053bf29-1daf-4b20-911a-f0fe6715859a" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditUpToRMB100000FromBankOfCommunicationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_d8abe0b1-fc91-4fd5-ab00-be66ed4d2dac" xlink:to="loc_acmr_LineOfCreditUpToRMB100000FromBankOfCommunicationsMember_6053bf29-1daf-4b20-911a-f0fe6715859a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust112023WithAnAnnualInterestRateOf360Member_2e85070e-7f06-4ac5-8a17-f12253d3d66a" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust112023WithAnAnnualInterestRateOf360Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB100000FromBankOfCommunicationsMember_6053bf29-1daf-4b20-911a-f0fe6715859a" xlink:to="loc_acmr_LineOfCreditDueOnAugust112023WithAnAnnualInterestRateOf360Member_2e85070e-7f06-4ac5-8a17-f12253d3d66a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnSeptember52023WithAnAnnualInterestRateOf350Member_e65818a0-2ed7-464e-91ff-6cedf18b85da" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnSeptember52023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB100000FromBankOfCommunicationsMember_6053bf29-1daf-4b20-911a-f0fe6715859a" xlink:to="loc_acmr_LineOfCreditDueOnSeptember52023WithAnAnnualInterestRateOf350Member_e65818a0-2ed7-464e-91ff-6cedf18b85da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_d8abe0b1-fc91-4fd5-ab00-be66ed4d2dac" xlink:to="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust262023WithAnAnnualInterestRateOf315Member_fc8a0017-8300-4a09-a715-f88b9ba87446" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust262023WithAnAnnualInterestRateOf315Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust262023WithAnAnnualInterestRateOf315Member_fc8a0017-8300-4a09-a715-f88b9ba87446" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditUpToRMB100000FromChinaMerchantsBankMember_dd233ab3-5f4e-4f43-8222-b5064f175242" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditUpToRMB100000FromChinaMerchantsBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditUpToRMB100000FromChinaMerchantsBankMember_dd233ab3-5f4e-4f43-8222-b5064f175242" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnJuly212023WithAnAnnualInterestRateOf350Member_f57f1bac-aa73-4bc9-a076-29aebe9888ff" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnJuly212023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnJuly212023WithAnAnnualInterestRateOf350Member_f57f1bac-aa73-4bc9-a076-29aebe9888ff" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnJuly272023WithAnAnnualInterestRateOf350Member_c6f3b61e-2766-47c5-b29b-ce700aecc6f4" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnJuly272023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnJuly272023WithAnAnnualInterestRateOf350Member_c6f3b61e-2766-47c5-b29b-ce700aecc6f4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust12023WithAnAnnualInterestRateOf350Member_cbbd1188-9b70-45a2-8166-0a89dd347e38" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust12023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust12023WithAnAnnualInterestRateOf350Member_cbbd1188-9b70-45a2-8166-0a89dd347e38" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust32023WithAnAnnualInterestRateOf350Member_6340127e-3778-402f-b06d-1772dc271278" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust32023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust32023WithAnAnnualInterestRateOf350Member_6340127e-3778-402f-b06d-1772dc271278" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust72023WithAnAnnualInterestRateOf350Member_e8025f1b-0961-4b3e-833d-e5e108661e60" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust72023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust72023WithAnAnnualInterestRateOf350Member_e8025f1b-0961-4b3e-833d-e5e108661e60" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust142023WithAnAnnualInterestRateOf350Member_3b695661-1c9c-4866-af4e-3037251a6ee2" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust142023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust142023WithAnAnnualInterestRateOf350Member_3b695661-1c9c-4866-af4e-3037251a6ee2" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust152023WithAnAnnualInterestRateOf350Member_ef5cc0cd-b1e0-4063-a672-eabe32e73c3b" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust152023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust152023WithAnAnnualInterestRateOf350Member_ef5cc0cd-b1e0-4063-a672-eabe32e73c3b" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust212023WithAnAnnualInterestRateOf350Member_c522f63b-e347-4ae2-b11f-6c4c6c0223af" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust212023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust212023WithAnAnnualInterestRateOf350Member_c522f63b-e347-4ae2-b11f-6c4c6c0223af" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnAugust282023WithAnAnnualInterestRateOf350Member_d570cb66-a2d8-4c19-b2ee-56e1411538ae" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnAugust282023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnAugust282023WithAnAnnualInterestRateOf350Member_d570cb66-a2d8-4c19-b2ee-56e1411538ae" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnSeptember132023WithAnAnnualInterestRateOf350Member_e579011d-da5f-43d4-b860-cd8bdd547ed9" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnSeptember132023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnSeptember132023WithAnAnnualInterestRateOf350Member_e579011d-da5f-43d4-b860-cd8bdd547ed9" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnSeptember202023WithAnAnnualInterestRateOf350Member_247d7bcb-1781-4a7d-8c82-405b83932577" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnSeptember202023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnSeptember202023WithAnAnnualInterestRateOf350Member_247d7bcb-1781-4a7d-8c82-405b83932577" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LineOfCreditDueOnSeptember292023WithAnAnnualInterestRateOf350Member_c6063df2-6ece-4c30-8842-4c7dec8be7eb" xlink:href="acmr-20230630.xsd#acmr_LineOfCreditDueOnSeptember292023WithAnAnnualInterestRateOf350Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LineOfCreditUpToRMB40000FromBankOfChinaMember_24adbcf3-6cce-41f0-a1e0-556bf4c4dae9" xlink:to="loc_acmr_LineOfCreditDueOnSeptember292023WithAnAnnualInterestRateOf350Member_c6063df2-6ece-4c30-8842-4c7dec8be7eb" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/LONGTERMBORROWINGSSummaryofLongtermBorrowingsDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#LONGTERMBORROWINGSSummaryofLongtermBorrowingsDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/LONGTERMBORROWINGSSummaryofLongtermBorrowingsDetails" xlink:type="extended" id="i1839512365ad426381cbaa2224aad6f5_LONGTERMBORROWINGSSummaryofLongtermBorrowingsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_74f94358-2aa8-40e0-a772-9a7539325f07" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongtermDebtCurrentAndNoncurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_74f94358-2aa8-40e0-a772-9a7539325f07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_f9f58536-a264-4fbb-9fd0-d3d8d233d517" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_74f94358-2aa8-40e0-a772-9a7539325f07" xlink:to="loc_us-gaap_LongTermDebt_f9f58536-a264-4fbb-9fd0-d3d8d233d517" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_cef9e793-da8c-4dc6-bd8f-5f71be9b58fc" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_74f94358-2aa8-40e0-a772-9a7539325f07" xlink:to="loc_us-gaap_LongTermDebtCurrent_cef9e793-da8c-4dc6-bd8f-5f71be9b58fc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_b5e1c4a1-b116-4984-82f0-4cc0442d7bd9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_74f94358-2aa8-40e0-a772-9a7539325f07" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_b5e1c4a1-b116-4984-82f0-4cc0442d7bd9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NumberOfInstallmentsForLoanRepayable_3d3341c6-67f4-4512-bf62-91f41f1c456d" xlink:href="acmr-20230630.xsd#acmr_NumberOfInstallmentsForLoanRepayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_acmr_NumberOfInstallmentsForLoanRepayable_3d3341c6-67f4-4512-bf62-91f41f1c456d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_88f72783-7e42-4cc6-a1f1-fb3fb7c14765" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_88f72783-7e42-4cc6-a1f1-fb3fb7c14765" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestCostsIncurred_68fab04f-74bb-4f3a-82e3-d81a8d7a632f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestCostsIncurred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_us-gaap_InterestCostsIncurred_68fab04f-74bb-4f3a-82e3-d81a8d7a632f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseLongTermDebt_8c72ba0b-3c92-4b72-a44e-4f1d6b2b34ca" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_us-gaap_InterestExpenseLongTermDebt_8c72ba0b-3c92-4b72-a44e-4f1d6b2b34ca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestCostsCapitalized_230b6dd8-4ad6-4db8-9cdd-0b5b76f099cb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestCostsCapitalized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_us-gaap_InterestCostsCapitalized_230b6dd8-4ad6-4db8-9cdd-0b5b76f099cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_52a0f456-b78e-40f7-b0cb-11842ba0553a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_e826175a-69dd-4511-aaab-3f09953d190d" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_52a0f456-b78e-40f7-b0cb-11842ba0553a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_c922bacd-3f5c-4486-8555-cd4d6501bc32" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_52a0f456-b78e-40f7-b0cb-11842ba0553a" xlink:to="loc_us-gaap_LineOfCreditFacilityAxis_c922bacd-3f5c-4486-8555-cd4d6501bc32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_c922bacd-3f5c-4486-8555-cd4d6501bc32_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_c922bacd-3f5c-4486-8555-cd4d6501bc32" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_c922bacd-3f5c-4486-8555-cd4d6501bc32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_75ec2571-2d2a-4ab8-8cb3-f5a0e5ad9fa9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_c922bacd-3f5c-4486-8555-cd4d6501bc32" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_75ec2571-2d2a-4ab8-8cb3-f5a0e5ad9fa9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ChinaMerchantsBankMember_0a243673-7710-4650-b6ae-c5b9156a7089" xlink:href="acmr-20230630.xsd#acmr_ChinaMerchantsBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_75ec2571-2d2a-4ab8-8cb3-f5a0e5ad9fa9" xlink:to="loc_acmr_ChinaMerchantsBankMember_0a243673-7710-4650-b6ae-c5b9156a7089" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_BankOfChinaMember_878cd0b8-86b1-4eb6-b767-92fa6a893de0" xlink:href="acmr-20230630.xsd#acmr_BankOfChinaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_75ec2571-2d2a-4ab8-8cb3-f5a0e5ad9fa9" xlink:to="loc_acmr_BankOfChinaMember_878cd0b8-86b1-4eb6-b767-92fa6a893de0" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/OTHERLONGTERMLIABILITIESDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#OTHERLONGTERMLIABILITIESDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/OTHERLONGTERMLIABILITIESDetails" xlink:type="extended" id="i97cab2ae9ed44a3989f6858bce4cc180_OTHERLONGTERMLIABILITIESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_dfe84004-9f8b-4229-8746-c781bca36ae8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_af872766-abc4-4d8f-8809-b24cc5737b17" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherLiabilitiesNoncurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_dfe84004-9f8b-4229-8746-c781bca36ae8" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_af872766-abc4-4d8f-8809-b24cc5737b17" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_dae2d60e-6522-4d66-a26f-900af5b736ad" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_af872766-abc4-4d8f-8809-b24cc5737b17" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_dae2d60e-6522-4d66-a26f-900af5b736ad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_6119aa1e-73c1-4831-8b83-87cf7379039d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_dfe84004-9f8b-4229-8746-c781bca36ae8" xlink:to="loc_us-gaap_DebtInstrumentTable_6119aa1e-73c1-4831-8b83-87cf7379039d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_47b0b5e7-0442-451a-9e2b-d0f8f6c5e3fe" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_6119aa1e-73c1-4831-8b83-87cf7379039d" xlink:to="loc_us-gaap_DebtInstrumentAxis_47b0b5e7-0442-451a-9e2b-d0f8f6c5e3fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_47b0b5e7-0442-451a-9e2b-d0f8f6c5e3fe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_47b0b5e7-0442-451a-9e2b-d0f8f6c5e3fe" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_47b0b5e7-0442-451a-9e2b-d0f8f6c5e3fe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_47b0b5e7-0442-451a-9e2b-d0f8f6c5e3fe" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SubsidiesToStressFreePolishingProjectMember_415bb9bb-b427-466e-b2c5-48b886f1df98" xlink:href="acmr-20230630.xsd#acmr_SubsidiesToStressFreePolishingProjectMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:to="loc_acmr_SubsidiesToStressFreePolishingProjectMember_415bb9bb-b427-466e-b2c5-48b886f1df98" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SubsidiesToElectroCopperPlatingProjectMember_f8b6b2ec-35be-40be-bf0c-2ad7d70259d1" xlink:href="acmr-20230630.xsd#acmr_SubsidiesToElectroCopperPlatingProjectMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:to="loc_acmr_SubsidiesToElectroCopperPlatingProjectMember_f8b6b2ec-35be-40be-bf0c-2ad7d70259d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SubsidiesToOtherCleaningToolsCommencedIn2020Member_e47e43ad-aa6c-44f4-b7bc-deda6db41f3b" xlink:href="acmr-20230630.xsd#acmr_SubsidiesToOtherCleaningToolsCommencedIn2020Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:to="loc_acmr_SubsidiesToOtherCleaningToolsCommencedIn2020Member_e47e43ad-aa6c-44f4-b7bc-deda6db41f3b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SubsidiesToSWLingangRDDevelopmentIn2021Member_4bd047ca-4975-4b84-ae5b-27a221748714" xlink:href="acmr-20230630.xsd#acmr_SubsidiesToSWLingangRDDevelopmentIn2021Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:to="loc_acmr_SubsidiesToSWLingangRDDevelopmentIn2021Member_4bd047ca-4975-4b84-ae5b-27a221748714" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SubsidiesToCO2TechnologyMember_39cbe708-b0c2-4927-84c4-939a1e0c67eb" xlink:href="acmr-20230630.xsd#acmr_SubsidiesToCO2TechnologyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:to="loc_acmr_SubsidiesToCO2TechnologyMember_39cbe708-b0c2-4927-84c4-939a1e0c67eb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_OtherMember_98b71834-f0b3-4818-a69a-cbce625fd8e9" xlink:href="acmr-20230630.xsd#acmr_OtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_2bf41645-69d2-49de-87b0-b0f97a02c444" xlink:to="loc_acmr_OtherMember_98b71834-f0b3-4818-a69a-cbce625fd8e9" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/LONGTERMINVESTMENTNarrativeDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#LONGTERMINVESTMENTNarrativeDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/LONGTERMINVESTMENTNarrativeDetails" xlink:type="extended" id="i5300dd5338b4438397cac740d3309c01_LONGTERMINVESTMENTNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LongTermInvestmentLineItems_64e19350-d5ad-4bf5-8220-9aa041cd9ba8" xlink:href="acmr-20230630.xsd#acmr_LongTermInvestmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsAbstract_2abcdb27-6239-4b2e-b933-c5313aea8a97" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LongTermInvestmentLineItems_64e19350-d5ad-4bf5-8220-9aa041cd9ba8" xlink:to="loc_us-gaap_InvestmentsAbstract_2abcdb27-6239-4b2e-b933-c5313aea8a97" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_aef603da-2944-4552-a63b-4379d3d6896e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2abcdb27-6239-4b2e-b933-c5313aea8a97" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_aef603da-2944-4552-a63b-4379d3d6896e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_1cbd37bb-158a-4933-9d0f-397ca1b2f422" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2abcdb27-6239-4b2e-b933-c5313aea8a97" xlink:to="loc_us-gaap_EquityMethodInvestments_1cbd37bb-158a-4933-9d0f-397ca1b2f422" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_ab17b777-933c-42ef-bd2b-d6f0bf973276" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2abcdb27-6239-4b2e-b933-c5313aea8a97" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_ab17b777-933c-42ef-bd2b-d6f0bf973276" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_b38e51c0-1014-44c9-a65e-61708170fda0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2abcdb27-6239-4b2e-b933-c5313aea8a97" xlink:to="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_b38e51c0-1014-44c9-a65e-61708170fda0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LongTermInvestmentsTable_ff7bad35-324b-4735-857d-c3fb2a4e5eef" xlink:href="acmr-20230630.xsd#acmr_LongTermInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_acmr_LongTermInvestmentLineItems_64e19350-d5ad-4bf5-8220-9aa041cd9ba8" xlink:to="loc_acmr_LongTermInvestmentsTable_ff7bad35-324b-4735-857d-c3fb2a4e5eef" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_03f451ae-2495-4f06-afd9-731589405f1e" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_LongTermInvestmentsTable_ff7bad35-324b-4735-857d-c3fb2a4e5eef" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_03f451ae-2495-4f06-afd9-731589405f1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_03f451ae-2495-4f06-afd9-731589405f1e_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_03f451ae-2495-4f06-afd9-731589405f1e" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_03f451ae-2495-4f06-afd9-731589405f1e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_ff293df4-fc70-4f5e-9145-8d459460e616" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_03f451ae-2495-4f06-afd9-731589405f1e" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_ff293df4-fc70-4f5e-9145-8d459460e616" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_EquityInvestmentMember_dd9564d9-16aa-4873-b9a5-9a0fb12d4de7" xlink:href="acmr-20230630.xsd#acmr_EquityInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_ff293df4-fc70-4f5e-9145-8d459460e616" xlink:to="loc_acmr_EquityInvestmentMember_dd9564d9-16aa-4873-b9a5-9a0fb12d4de7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7635fc5e-e20a-4804-a5bb-d36cbd0171d3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_LongTermInvestmentsTable_ff7bad35-324b-4735-857d-c3fb2a4e5eef" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7635fc5e-e20a-4804-a5bb-d36cbd0171d3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_7635fc5e-e20a-4804-a5bb-d36cbd0171d3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7635fc5e-e20a-4804-a5bb-d36cbd0171d3" xlink:to="loc_us-gaap_RelatedPartyDomain_7635fc5e-e20a-4804-a5bb-d36cbd0171d3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7635fc5e-e20a-4804-a5bb-d36cbd0171d3" xlink:to="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NinebellCompanyLimitedMember_c8e04227-3b5f-413c-9e28-193ddd6c4cbd" xlink:href="acmr-20230630.xsd#acmr_NinebellCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:to="loc_acmr_NinebellCompanyLimitedMember_c8e04227-3b5f-413c-9e28-193ddd6c4cbd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_WooilFluconCompanyLimitedMember_c6292b33-7aa8-41b2-8247-0ac11ecf44d2" xlink:href="acmr-20230630.xsd#acmr_WooilFluconCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:to="loc_acmr_WooilFluconCompanyLimitedMember_c6292b33-7aa8-41b2-8247-0ac11ecf44d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember_243e5bc9-ef87-4dab-ad42-a4b8446bb100" xlink:href="acmr-20230630.xsd#acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:to="loc_acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember_243e5bc9-ef87-4dab-ad42-a4b8446bb100" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember_6f4c7afa-0569-4ce1-b4c1-72d09eaf6424" xlink:href="acmr-20230630.xsd#acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:to="loc_acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember_6f4c7afa-0569-4ce1-b4c1-72d09eaf6424" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_WaferworksCompanyLimitedMember_bcfed9ae-b7b5-4d54-9d7c-dde471f1ed95" xlink:href="acmr-20230630.xsd#acmr_WaferworksCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_5bf43c3c-4ee4-4416-af48-49c3ad0141d5" xlink:to="loc_acmr_WaferworksCompanyLimitedMember_bcfed9ae-b7b5-4d54-9d7c-dde471f1ed95" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_3b353890-eb37-4e7f-bd9c-bc5e5c205d49" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_LongTermInvestmentsTable_ff7bad35-324b-4735-857d-c3fb2a4e5eef" xlink:to="loc_us-gaap_StatementClassOfStockAxis_3b353890-eb37-4e7f-bd9c-bc5e5c205d49" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_3b353890-eb37-4e7f-bd9c-bc5e5c205d49_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_3b353890-eb37-4e7f-bd9c-bc5e5c205d49" xlink:to="loc_us-gaap_ClassOfStockDomain_3b353890-eb37-4e7f-bd9c-bc5e5c205d49_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_f375a3ad-c5fb-4e80-a532-8331a144cff0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_3b353890-eb37-4e7f-bd9c-bc5e5c205d49" xlink:to="loc_us-gaap_ClassOfStockDomain_f375a3ad-c5fb-4e80-a532-8331a144cff0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_cb317624-cfd9-4bfb-892d-682a2c6a47d3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_f375a3ad-c5fb-4e80-a532-8331a144cff0" xlink:to="loc_us-gaap_CommonClassAMember_cb317624-cfd9-4bfb-892d-682a2c6a47d3" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/LONGTERMINVESTMENTSummaryofLongTermInvestmentsDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#LONGTERMINVESTMENTSummaryofLongTermInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/LONGTERMINVESTMENTSummaryofLongTermInvestmentsDetails" xlink:type="extended" id="i8afc0da16d0349deb8f2d328f3e69af0_LONGTERMINVESTMENTSummaryofLongTermInvestmentsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LongTermInvestmentsLineItems_392c738c-2f6f-4d10-ba60-d06eb39d416c" xlink:href="acmr-20230630.xsd#acmr_LongTermInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_20290879-d58e-4c8e-8c0c-9915a9d4af8e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_LongTermInvestmentsLineItems_392c738c-2f6f-4d10-ba60-d06eb39d416c" xlink:to="loc_us-gaap_LongTermInvestments_20290879-d58e-4c8e-8c0c-9915a9d4af8e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LongTermInvestmentsTable_6288c126-18f3-430f-8759-3f63ff47ff9d" xlink:href="acmr-20230630.xsd#acmr_LongTermInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_acmr_LongTermInvestmentsLineItems_392c738c-2f6f-4d10-ba60-d06eb39d416c" xlink:to="loc_acmr_LongTermInvestmentsTable_6288c126-18f3-430f-8759-3f63ff47ff9d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_cb511bd0-4e59-4a9e-85e9-246c4fbc5edc" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_LongTermInvestmentsTable_6288c126-18f3-430f-8759-3f63ff47ff9d" xlink:to="loc_us-gaap_InvestmentTypeAxis_cb511bd0-4e59-4a9e-85e9-246c4fbc5edc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_cb511bd0-4e59-4a9e-85e9-246c4fbc5edc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_cb511bd0-4e59-4a9e-85e9-246c4fbc5edc" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_cb511bd0-4e59-4a9e-85e9-246c4fbc5edc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_500a64ac-32d9-4de6-8851-1d83da05c44b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_cb511bd0-4e59-4a9e-85e9-246c4fbc5edc" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_500a64ac-32d9-4de6-8851-1d83da05c44b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_InvestmentExcludingOtherMember_fc9db7f8-b20e-4c19-9b96-e236ed396212" xlink:href="acmr-20230630.xsd#acmr_InvestmentExcludingOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_500a64ac-32d9-4de6-8851-1d83da05c44b" xlink:to="loc_acmr_InvestmentExcludingOtherMember_fc9db7f8-b20e-4c19-9b96-e236ed396212" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLongTermInvestmentsMember_636adec5-dcc0-43f8-a0c6-187e84ead6fd" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherLongTermInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_500a64ac-32d9-4de6-8851-1d83da05c44b" xlink:to="loc_us-gaap_OtherLongTermInvestmentsMember_636adec5-dcc0-43f8-a0c6-187e84ead6fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_529400e6-10ac-4a30-9a9c-cec95077152e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_LongTermInvestmentsTable_6288c126-18f3-430f-8759-3f63ff47ff9d" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_529400e6-10ac-4a30-9a9c-cec95077152e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_529400e6-10ac-4a30-9a9c-cec95077152e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_529400e6-10ac-4a30-9a9c-cec95077152e" xlink:to="loc_us-gaap_RelatedPartyDomain_529400e6-10ac-4a30-9a9c-cec95077152e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_529400e6-10ac-4a30-9a9c-cec95077152e" xlink:to="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NinebellCompanyLimitedMember_c88d95c9-6f55-4ded-b4ed-b3405d662467" xlink:href="acmr-20230630.xsd#acmr_NinebellCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:to="loc_acmr_NinebellCompanyLimitedMember_c88d95c9-6f55-4ded-b4ed-b3405d662467" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_WooilFluconCompanyLimitedMember_a637cf5a-357b-4a5d-813a-a6abe0c08209" xlink:href="acmr-20230630.xsd#acmr_WooilFluconCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:to="loc_acmr_WooilFluconCompanyLimitedMember_a637cf5a-357b-4a5d-813a-a6abe0c08209" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember_3d507d2a-b189-461c-a43f-ae5fcbeda57e" xlink:href="acmr-20230630.xsd#acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:to="loc_acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember_3d507d2a-b189-461c-a43f-ae5fcbeda57e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember_f225dc41-e733-4251-bc4c-34973b482aa9" xlink:href="acmr-20230630.xsd#acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:to="loc_acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember_f225dc41-e733-4251-bc4c-34973b482aa9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_WaferworksCompanyLimitedMember_7d378d40-6635-4611-acfb-9eb512db4bc5" xlink:href="acmr-20230630.xsd#acmr_WaferworksCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:to="loc_acmr_WaferworksCompanyLimitedMember_7d378d40-6635-4611-acfb-9eb512db4bc5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_TDSHFundMember_49088730-2f79-4731-af17-c7c7b9a834eb" xlink:href="acmr-20230630.xsd#acmr_TDSHFundMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_40aa908e-f596-44b5-9789-849fa38b2655" xlink:to="loc_acmr_TDSHFundMember_49088730-2f79-4731-af17-c7c7b9a834eb" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/TRADINGSECURITIESNarrativeDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#TRADINGSECURITIESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/TRADINGSECURITIESNarrativeDetails" xlink:type="extended" id="i0e2b0ee5d8fb4ffb8d61577102c01ea7_TRADINGSECURITIESNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_7e982d3c-908c-4a93-bdac-4017cb1bf03d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsAbstract_2846c3c4-4535-4b52-9807-c9a7320ba2c7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_7e982d3c-908c-4a93-bdac-4017cb1bf03d" xlink:to="loc_us-gaap_InvestmentsAbstract_2846c3c4-4535-4b52-9807-c9a7320ba2c7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_InvestmentInPartnership_92b156d1-feb3-4382-9782-48193f746daf" xlink:href="acmr-20230630.xsd#acmr_InvestmentInPartnership"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2846c3c4-4535-4b52-9807-c9a7320ba2c7" xlink:to="loc_acmr_InvestmentInPartnership_92b156d1-feb3-4382-9782-48193f746daf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_OwnershipPercentageInPartnership_4a701051-34c4-4c84-8043-1df24e704b38" xlink:href="acmr-20230630.xsd#acmr_OwnershipPercentageInPartnership"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2846c3c4-4535-4b52-9807-c9a7320ba2c7" xlink:to="loc_acmr_OwnershipPercentageInPartnership_4a701051-34c4-4c84-8043-1df24e704b38" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_345b8e29-a3eb-4077-8f03-853877ff4164" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2846c3c4-4535-4b52-9807-c9a7320ba2c7" xlink:to="loc_us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_345b8e29-a3eb-4077-8f03-853877ff4164" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecuritiesRealizedGainLossExcludingOtherThanTemporaryImpairments_64b994e5-223d-4396-9d0e-ba90338a563a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MarketableSecuritiesRealizedGainLossExcludingOtherThanTemporaryImpairments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsAbstract_2846c3c4-4535-4b52-9807-c9a7320ba2c7" xlink:to="loc_us-gaap_MarketableSecuritiesRealizedGainLossExcludingOtherThanTemporaryImpairments_64b994e5-223d-4396-9d0e-ba90338a563a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_cd52bbf7-93df-4355-a937-1d57de6e1881" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_7e982d3c-908c-4a93-bdac-4017cb1bf03d" xlink:to="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_cd52bbf7-93df-4355-a937-1d57de6e1881" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7c4deb50-9478-467d-8e86-9189f0b12ec2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_cd52bbf7-93df-4355-a937-1d57de6e1881" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7c4deb50-9478-467d-8e86-9189f0b12ec2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_7c4deb50-9478-467d-8e86-9189f0b12ec2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7c4deb50-9478-467d-8e86-9189f0b12ec2" xlink:to="loc_us-gaap_RelatedPartyDomain_7c4deb50-9478-467d-8e86-9189f0b12ec2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_c20fbce4-d6f6-4aaa-a22e-15f9b129ca28" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7c4deb50-9478-467d-8e86-9189f0b12ec2" xlink:to="loc_us-gaap_RelatedPartyDomain_c20fbce4-d6f6-4aaa-a22e-15f9b129ca28" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_SemiconductorManufacturingInternationalCorporationMember_d8c8a6a7-6bd6-4f0e-a6bd-d3d0e333900f" xlink:href="acmr-20230630.xsd#acmr_SemiconductorManufacturingInternationalCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_c20fbce4-d6f6-4aaa-a22e-15f9b129ca28" xlink:to="loc_acmr_SemiconductorManufacturingInternationalCorporationMember_d8c8a6a7-6bd6-4f0e-a6bd-d3d0e333900f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NuodeAssetManagementCompanyLimitedMember_b88acd93-8f70-46e1-950c-28deadead851" xlink:href="acmr-20230630.xsd#acmr_NuodeAssetManagementCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_c20fbce4-d6f6-4aaa-a22e-15f9b129ca28" xlink:to="loc_acmr_NuodeAssetManagementCompanyLimitedMember_b88acd93-8f70-46e1-950c-28deadead851" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_880c91c6-3662-4fac-9eae-31cc9c5929b1" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_cd52bbf7-93df-4355-a937-1d57de6e1881" xlink:to="loc_srt_RangeAxis_880c91c6-3662-4fac-9eae-31cc9c5929b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_880c91c6-3662-4fac-9eae-31cc9c5929b1_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_880c91c6-3662-4fac-9eae-31cc9c5929b1" xlink:to="loc_srt_RangeMember_880c91c6-3662-4fac-9eae-31cc9c5929b1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_6d0b3c19-bcee-4e29-bd40-fb380d6de69f" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_880c91c6-3662-4fac-9eae-31cc9c5929b1" xlink:to="loc_srt_RangeMember_6d0b3c19-bcee-4e29-bd40-fb380d6de69f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_a210429d-6866-413e-afd7-bdc683123512" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_6d0b3c19-bcee-4e29-bd40-fb380d6de69f" xlink:to="loc_srt_MinimumMember_a210429d-6866-413e-afd7-bdc683123512" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/RELATEDPARTYBALANCESANDTRANSACTIONSDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#RELATEDPARTYBALANCESANDTRANSACTIONSDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/RELATEDPARTYBALANCESANDTRANSACTIONSDetails" xlink:type="extended" id="i96f2642bf76946e8bdbee886470a208d_RELATEDPARTYBALANCESANDTRANSACTIONSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_b5a4be65-99f6-49c3-9830-aaa8fc6480a2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_48318ecf-007e-4c78-a5e1-976d0b89965a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5a4be65-99f6-49c3-9830-aaa8fc6480a2" xlink:to="loc_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_48318ecf-007e-4c78-a5e1-976d0b89965a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivablesNetCurrent_ca5d5b88-c789-49e2-90b7-594160c9854d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherReceivablesNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5a4be65-99f6-49c3-9830-aaa8fc6480a2" xlink:to="loc_us-gaap_OtherReceivablesNetCurrent_ca5d5b88-c789-49e2-90b7-594160c9854d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_c2106f06-8799-439c-84c5-bdfa22bc0bc1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5a4be65-99f6-49c3-9830-aaa8fc6480a2" xlink:to="loc_us-gaap_AccountsPayableCurrent_c2106f06-8799-439c-84c5-bdfa22bc0bc1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenue_26709749-9df5-4d01-bf95-045f647321f7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CostOfRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5a4be65-99f6-49c3-9830-aaa8fc6480a2" xlink:to="loc_us-gaap_CostOfRevenue_26709749-9df5-4d01-bf95-045f647321f7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_1e46227d-f854-43a0-9841-44c24b15bf2a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_b5a4be65-99f6-49c3-9830-aaa8fc6480a2" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_1e46227d-f854-43a0-9841-44c24b15bf2a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_0d75a356-d369-44dd-a1b5-666c610af14a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_1e46227d-f854-43a0-9841-44c24b15bf2a" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_0d75a356-d369-44dd-a1b5-666c610af14a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_0d75a356-d369-44dd-a1b5-666c610af14a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_0d75a356-d369-44dd-a1b5-666c610af14a" xlink:to="loc_us-gaap_RelatedPartyDomain_0d75a356-d369-44dd-a1b5-666c610af14a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_d437aa8a-c7a3-43a6-abbf-e51341c34eae" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_0d75a356-d369-44dd-a1b5-666c610af14a" xlink:to="loc_us-gaap_RelatedPartyDomain_d437aa8a-c7a3-43a6-abbf-e51341c34eae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_4071422c-8e58-41b9-a041-db943fc2d055" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_d437aa8a-c7a3-43a6-abbf-e51341c34eae" xlink:to="loc_us-gaap_RelatedPartyMember_4071422c-8e58-41b9-a041-db943fc2d055" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_a1ab56ae-da0f-472a-8da6-b607cc0d07eb" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_1e46227d-f854-43a0-9841-44c24b15bf2a" xlink:to="loc_srt_CounterpartyNameAxis_a1ab56ae-da0f-472a-8da6-b607cc0d07eb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_a1ab56ae-da0f-472a-8da6-b607cc0d07eb_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_a1ab56ae-da0f-472a-8da6-b607cc0d07eb" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_a1ab56ae-da0f-472a-8da6-b607cc0d07eb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_a88f1354-bb3b-4b65-8d37-db9b8947ce51" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_a1ab56ae-da0f-472a-8da6-b607cc0d07eb" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_a88f1354-bb3b-4b65-8d37-db9b8947ce51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NinebellCoLtdMember_c21991b5-3c79-4153-b0d8-787491afe96a" xlink:href="acmr-20230630.xsd#acmr_NinebellCoLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_a88f1354-bb3b-4b65-8d37-db9b8947ce51" xlink:to="loc_acmr_NinebellCoLtdMember_c21991b5-3c79-4153-b0d8-787491afe96a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengyiSemiconductorTechnologyCoLtdMember_f44f2ca0-8718-4e2d-8d7e-5f64e59fa7c7" xlink:href="acmr-20230630.xsd#acmr_ShengyiSemiconductorTechnologyCoLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_a88f1354-bb3b-4b65-8d37-db9b8947ce51" xlink:to="loc_acmr_ShengyiSemiconductorTechnologyCoLtdMember_f44f2ca0-8718-4e2d-8d7e-5f64e59fa7c7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/COMMONSTOCKDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#COMMONSTOCKDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/COMMONSTOCKDetails" xlink:type="extended" id="i9f9ddc463e454cd0a1019f883872ed39_COMMONSTOCKDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_331b5a7b-f146-485d-9353-e939e4280de0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDisclosuresAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_331b5a7b-f146-485d-9353-e939e4280de0" xlink:to="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_3b141004-6de0-4752-8ea9-dacaf4cc4ca2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_3b141004-6de0-4752-8ea9-dacaf4cc4ca2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_3b35bd59-ef0a-493a-a657-348e57904ead" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_3b35bd59-ef0a-493a-a657-348e57904ead" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_VotingRightsPerShare_a334c3be-3b95-4f35-baf6-0122436d60ba" xlink:href="acmr-20230630.xsd#acmr_VotingRightsPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_acmr_VotingRightsPerShare_a334c3be-3b95-4f35-baf6-0122436d60ba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConversionOfStockSharesConverted1_31acb2b6-ad28-4386-97b4-159f498fa8e9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConversionOfStockSharesConverted1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_ConversionOfStockSharesConverted1_31acb2b6-ad28-4386-97b4-159f498fa8e9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_6d75b35a-a32a-464a-b8fb-3d7528ef205e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_6d75b35a-a32a-464a-b8fb-3d7528ef205e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_2ffea2a5-6bb8-4323-99c0-a54e662a341a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_2ffea2a5-6bb8-4323-99c0-a54e662a341a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_cedf49f8-62ca-40e8-b16d-f12f843be264" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_CommonStockSharesIssued_cedf49f8-62ca-40e8-b16d-f12f843be264" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_2397fcb0-fac2-41a8-ba36-2c2580c16dd3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDisclosuresAbstract_7ba2210d-80ea-4dd6-a74f-39d13a2031ac" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_2397fcb0-fac2-41a8-ba36-2c2580c16dd3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_d8c16fad-3117-4d6a-ace9-6b88d4576621" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_331b5a7b-f146-485d-9353-e939e4280de0" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_d8c16fad-3117-4d6a-ace9-6b88d4576621" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_ed1fbb32-ec4b-4ef5-8abe-960f68ac4074" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_d8c16fad-3117-4d6a-ace9-6b88d4576621" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_ed1fbb32-ec4b-4ef5-8abe-960f68ac4074" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_ed1fbb32-ec4b-4ef5-8abe-960f68ac4074_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_ed1fbb32-ec4b-4ef5-8abe-960f68ac4074" xlink:to="loc_us-gaap_EquityComponentDomain_ed1fbb32-ec4b-4ef5-8abe-960f68ac4074_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_4769ec22-99f2-45e8-af31-3c34cdaab8f8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_ed1fbb32-ec4b-4ef5-8abe-960f68ac4074" xlink:to="loc_us-gaap_EquityComponentDomain_4769ec22-99f2-45e8-af31-3c34cdaab8f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_0cac5345-e398-448d-8415-aa0fa7f6a88d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_4769ec22-99f2-45e8-af31-3c34cdaab8f8" xlink:to="loc_us-gaap_CommonStockMember_0cac5345-e398-448d-8415-aa0fa7f6a88d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_a17e319c-ca57-4f68-ba6b-1f179e3b1856" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_d8c16fad-3117-4d6a-ace9-6b88d4576621" xlink:to="loc_us-gaap_StatementClassOfStockAxis_a17e319c-ca57-4f68-ba6b-1f179e3b1856" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_a17e319c-ca57-4f68-ba6b-1f179e3b1856_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_a17e319c-ca57-4f68-ba6b-1f179e3b1856" xlink:to="loc_us-gaap_ClassOfStockDomain_a17e319c-ca57-4f68-ba6b-1f179e3b1856_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_3e2e3c78-cf81-4bd1-b9bd-8bcb27d6efc3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_a17e319c-ca57-4f68-ba6b-1f179e3b1856" xlink:to="loc_us-gaap_ClassOfStockDomain_3e2e3c78-cf81-4bd1-b9bd-8bcb27d6efc3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_bdb0871f-e484-403a-9be8-489bcdb12e16" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_3e2e3c78-cf81-4bd1-b9bd-8bcb27d6efc3" xlink:to="loc_us-gaap_CommonClassAMember_bdb0871f-e484-403a-9be8-489bcdb12e16" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassBMember_199ff030-81d5-41fa-aa08-b03ab3e571ad" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonClassBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_3e2e3c78-cf81-4bd1-b9bd-8bcb27d6efc3" xlink:to="loc_us-gaap_CommonClassBMember_199ff030-81d5-41fa-aa08-b03ab3e571ad" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/STOCKBASEDCOMPENSATIONStockbasedCompensationExpenseDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#STOCKBASEDCOMPENSATIONStockbasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/STOCKBASEDCOMPENSATIONStockbasedCompensationExpenseDetails" xlink:type="extended" id="i09d2c1ae90c84d60b1bec6cf52fc2b12_STOCKBASEDCOMPENSATIONStockbasedCompensationExpenseDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_430f218c-3fd7-4e11-88fe-cce89325ebeb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAbstract_2b74247c-ca5a-4e9c-9518-7f9b3043ed77" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_430f218c-3fd7-4e11-88fe-cce89325ebeb" xlink:to="loc_us-gaap_ShareBasedCompensationAbstract_2b74247c-ca5a-4e9c-9518-7f9b3043ed77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_48d6dd9e-63b6-453a-b377-7486c834f24a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationAbstract_2b74247c-ca5a-4e9c-9518-7f9b3043ed77" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_48d6dd9e-63b6-453a-b377-7486c834f24a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_b36ec74d-4449-413a-a521-3d21e3f075ba" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_430f218c-3fd7-4e11-88fe-cce89325ebeb" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_b36ec74d-4449-413a-a521-3d21e3f075ba" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_5bd7d86e-df95-499e-ba29-1fbed64997fd" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_b36ec74d-4449-413a-a521-3d21e3f075ba" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_5bd7d86e-df95-499e-ba29-1fbed64997fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_5bd7d86e-df95-499e-ba29-1fbed64997fd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_5bd7d86e-df95-499e-ba29-1fbed64997fd" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_5bd7d86e-df95-499e-ba29-1fbed64997fd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_c11299bd-acd8-420e-b0b7-58521e10eeed" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_5bd7d86e-df95-499e-ba29-1fbed64997fd" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_c11299bd-acd8-420e-b0b7-58521e10eeed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfSalesMember_4cdfd2e7-d725-4fc7-a059-66871e504dce" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CostOfSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c11299bd-acd8-420e-b0b7-58521e10eeed" xlink:to="loc_us-gaap_CostOfSalesMember_4cdfd2e7-d725-4fc7-a059-66871e504dce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_6df6f2c3-8699-47d1-adfc-e2002ed96992" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c11299bd-acd8-420e-b0b7-58521e10eeed" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_6df6f2c3-8699-47d1-adfc-e2002ed96992" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_f93338aa-3fac-42ec-875e-0ff6166351a0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ResearchAndDevelopmentExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c11299bd-acd8-420e-b0b7-58521e10eeed" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseMember_f93338aa-3fac-42ec-875e-0ff6166351a0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_16f9d38c-9bc6-4afb-83e0-bfc50c2b6c8e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c11299bd-acd8-420e-b0b7-58521e10eeed" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_16f9d38c-9bc6-4afb-83e0-bfc50c2b6c8e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_68a259f3-bfcd-4c63-a3f3-bd3d47af55b6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_b36ec74d-4449-413a-a521-3d21e3f075ba" xlink:to="loc_us-gaap_AwardTypeAxis_68a259f3-bfcd-4c63-a3f3-bd3d47af55b6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_68a259f3-bfcd-4c63-a3f3-bd3d47af55b6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_68a259f3-bfcd-4c63-a3f3-bd3d47af55b6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_68a259f3-bfcd-4c63-a3f3-bd3d47af55b6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_598254aa-ae2d-4e28-bd51-be2ff3088723" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_68a259f3-bfcd-4c63-a3f3-bd3d47af55b6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_598254aa-ae2d-4e28-bd51-be2ff3088723" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_f0cecf59-22b4-47e5-ae8e-593619f20370" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_598254aa-ae2d-4e28-bd51-be2ff3088723" xlink:to="loc_us-gaap_EmployeeStockOptionMember_f0cecf59-22b4-47e5-ae8e-593619f20370" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember_bfcfa59d-242e-4ee0-a3a6-5154576a5234" xlink:href="acmr-20230630.xsd#acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_598254aa-ae2d-4e28-bd51-be2ff3088723" xlink:to="loc_acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember_bfcfa59d-242e-4ee0-a3a6-5154576a5234" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_5c7df3b1-b5d8-451f-bfe8-fb3c9e84cda3" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_b36ec74d-4449-413a-a521-3d21e3f075ba" xlink:to="loc_srt_ConsolidatedEntitiesAxis_5c7df3b1-b5d8-451f-bfe8-fb3c9e84cda3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_5c7df3b1-b5d8-451f-bfe8-fb3c9e84cda3_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_5c7df3b1-b5d8-451f-bfe8-fb3c9e84cda3" xlink:to="loc_srt_ConsolidatedEntitiesDomain_5c7df3b1-b5d8-451f-bfe8-fb3c9e84cda3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_1056e859-46ac-4a7c-8d78-172cddfc3238" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_5c7df3b1-b5d8-451f-bfe8-fb3c9e84cda3" xlink:to="loc_srt_ConsolidatedEntitiesDomain_1056e859-46ac-4a7c-8d78-172cddfc3238" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchShanghaiIncMember_6454e2ae-b3b2-4aab-b908-a4eb99a3f76f" xlink:href="acmr-20230630.xsd#acmr_ACMResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_1056e859-46ac-4a7c-8d78-172cddfc3238" xlink:to="loc_acmr_ACMResearchShanghaiIncMember_6454e2ae-b3b2-4aab-b908-a4eb99a3f76f" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/STOCKBASEDCOMPENSATIONShareOptionActivitiesDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#STOCKBASEDCOMPENSATIONShareOptionActivitiesDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/STOCKBASEDCOMPENSATIONShareOptionActivitiesDetails" xlink:type="extended" id="ice144a9f9f5243f2b8bc45d62cbc3cc1_STOCKBASEDCOMPENSATIONShareOptionActivitiesDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3dc96009-ff5a-4f2b-9486-13987e6f8e54" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3dc96009-ff5a-4f2b-9486-13987e6f8e54" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_5f368895-6f3a-4bbf-bb15-f2e4779b2ba5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3dc96009-ff5a-4f2b-9486-13987e6f8e54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_5f368895-6f3a-4bbf-bb15-f2e4779b2ba5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_7c912e11-c598-403c-ae2d-c5386ce5987c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3dc96009-ff5a-4f2b-9486-13987e6f8e54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_7c912e11-c598-403c-ae2d-c5386ce5987c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_83d1f192-25e3-497b-bd9a-4a1e4fabdbf1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3dc96009-ff5a-4f2b-9486-13987e6f8e54" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_83d1f192-25e3-497b-bd9a-4a1e4fabdbf1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_f7e9350a-559b-4667-be32-18df36fde0b8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3dc96009-ff5a-4f2b-9486-13987e6f8e54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_f7e9350a-559b-4667-be32-18df36fde0b8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_18b56104-f445-4268-89cb-eead22c5e828" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_7e76f0fe-cc32-4fdd-8d59-ee3946217f00" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_7e76f0fe-cc32-4fdd-8d59-ee3946217f00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_1b7627fe-71ad-48d4-a2cb-a495286e0056" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_1b7627fe-71ad-48d4-a2cb-a495286e0056" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_5d21ba11-1410-4f29-a821-6ddf234ca30f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_1b7627fe-71ad-48d4-a2cb-a495286e0056" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_5d21ba11-1410-4f29-a821-6ddf234ca30f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_5a884dc1-033d-447a-9ee7-c3562500b339" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_1b7627fe-71ad-48d4-a2cb-a495286e0056" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_5a884dc1-033d-447a-9ee7-c3562500b339" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_7f07cb28-67b4-47f4-8762-49aaa80f674d" xlink:href="acmr-20230630.xsd#acmr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_1b7627fe-71ad-48d4-a2cb-a495286e0056" xlink:to="loc_acmr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_7f07cb28-67b4-47f4-8762-49aaa80f674d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue_6936a647-5ab4-4429-81ba-12ab0f27dbc7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueAbstract_1b7627fe-71ad-48d4-a2cb-a495286e0056" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue_6936a647-5ab4-4429-81ba-12ab0f27dbc7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_c8497c56-ed47-4492-8837-22d308bec13e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_c0e19d8f-d9bc-4dec-98cf-552aaaa9dc27" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_c0e19d8f-d9bc-4dec-98cf-552aaaa9dc27" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_bfa946ad-a544-48fa-9db6-f79ade1fa099" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_c0e19d8f-d9bc-4dec-98cf-552aaaa9dc27" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_bfa946ad-a544-48fa-9db6-f79ade1fa099" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_d08b4e2d-0e55-42d7-ad45-2811fe66fff4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_c0e19d8f-d9bc-4dec-98cf-552aaaa9dc27" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_d08b4e2d-0e55-42d7-ad45-2811fe66fff4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_f7f19cd5-c441-4e5e-b9d6-fefd9ef38c22" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_c0e19d8f-d9bc-4dec-98cf-552aaaa9dc27" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_f7f19cd5-c441-4e5e-b9d6-fefd9ef38c22" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_dcac799f-a056-4753-a32b-176896bf8bb8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_c0e19d8f-d9bc-4dec-98cf-552aaaa9dc27" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_dcac799f-a056-4753-a32b-176896bf8bb8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_ef7934d3-34bf-4a00-ab40-0c82781c584e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_1d86c5cc-6afa-4018-b85e-93f5d83f043a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_1d86c5cc-6afa-4018-b85e-93f5d83f043a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_6137c8a3-dc14-42f8-a36f-f728530e567b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_1d86c5cc-6afa-4018-b85e-93f5d83f043a" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_6137c8a3-dc14-42f8-a36f-f728530e567b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_6c21d312-f36d-47dc-b082-1073723928c9" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_6c21d312-f36d-47dc-b082-1073723928c9" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_d729360f-91d8-4110-b0d0-e43f51aa8b0c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_d729360f-91d8-4110-b0d0-e43f51aa8b0c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_fb07e777-c0a4-44a2-9f77-0ffd7390de08" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2eac366c-faa1-40b6-a095-9a98f957b854" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_fb07e777-c0a4-44a2-9f77-0ffd7390de08" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_322fd157-36bb-4cbc-b1d7-28e5006d8345" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_fb07e777-c0a4-44a2-9f77-0ffd7390de08" xlink:to="loc_us-gaap_AwardTypeAxis_322fd157-36bb-4cbc-b1d7-28e5006d8345" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_322fd157-36bb-4cbc-b1d7-28e5006d8345_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_322fd157-36bb-4cbc-b1d7-28e5006d8345" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_322fd157-36bb-4cbc-b1d7-28e5006d8345_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_54196c77-cb53-4400-94a0-00080bfbbacb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_322fd157-36bb-4cbc-b1d7-28e5006d8345" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_54196c77-cb53-4400-94a0-00080bfbbacb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_89ee5efa-a947-4c2e-aa62-16a8c4770404" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_54196c77-cb53-4400-94a0-00080bfbbacb" xlink:to="loc_us-gaap_EmployeeStockOptionMember_89ee5efa-a947-4c2e-aa62-16a8c4770404" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember_63c42a7b-9835-4971-abcb-225cd2f17a13" xlink:href="acmr-20230630.xsd#acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_54196c77-cb53-4400-94a0-00080bfbbacb" xlink:to="loc_acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember_63c42a7b-9835-4971-abcb-225cd2f17a13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_b9d018cb-1194-4bc9-a125-9eb0d0f40f1f" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_fb07e777-c0a4-44a2-9f77-0ffd7390de08" xlink:to="loc_srt_ConsolidatedEntitiesAxis_b9d018cb-1194-4bc9-a125-9eb0d0f40f1f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_b9d018cb-1194-4bc9-a125-9eb0d0f40f1f_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_b9d018cb-1194-4bc9-a125-9eb0d0f40f1f" xlink:to="loc_srt_ConsolidatedEntitiesDomain_b9d018cb-1194-4bc9-a125-9eb0d0f40f1f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_ed7cde27-3610-4ec4-b187-026919d22f70" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_b9d018cb-1194-4bc9-a125-9eb0d0f40f1f" xlink:to="loc_srt_ConsolidatedEntitiesDomain_ed7cde27-3610-4ec4-b187-026919d22f70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchShanghaiIncMember_9ec8da8b-6c18-4b2b-bcdf-3fc5554813c5" xlink:href="acmr-20230630.xsd#acmr_ACMResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_ed7cde27-3610-4ec4-b187-026919d22f70" xlink:to="loc_acmr_ACMResearchShanghaiIncMember_9ec8da8b-6c18-4b2b-bcdf-3fc5554813c5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/STOCKBASEDCOMPENSATIONAssumptionsUsedtoDetermineFairValueofShareOptionsGrantedDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#STOCKBASEDCOMPENSATIONAssumptionsUsedtoDetermineFairValueofShareOptionsGrantedDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/STOCKBASEDCOMPENSATIONAssumptionsUsedtoDetermineFairValueofShareOptionsGrantedDetails" xlink:type="extended" id="ifcbc368cea494bbb9fed9f067e67bff8_STOCKBASEDCOMPENSATIONAssumptionsUsedtoDetermineFairValueofShareOptionsGrantedDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_b0c4ab93-97e7-4b8e-acc9-bb2599224f30" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_b0c4ab93-97e7-4b8e-acc9-bb2599224f30" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharePrice_d87dac70-13a2-4b0b-aa86-97f8c649925d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:to="loc_us-gaap_SharePrice_d87dac70-13a2-4b0b-aa86-97f8c649925d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_3dd987b6-42d2-4045-ad65-27b064feebca" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_3dd987b6-42d2-4045-ad65-27b064feebca" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_1b345863-0eb4-4ff5-aad1-c5f2dfdbeb8f" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_1b345863-0eb4-4ff5-aad1-c5f2dfdbeb8f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_9843ac4c-71a9-4b8d-875b-bf9af2b097f0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_9843ac4c-71a9-4b8d-875b-bf9af2b097f0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_537793d2-d385-4dba-8620-2d8bccdf2bfb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_feff24b8-da38-4116-91a9-d282cea924b5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_537793d2-d385-4dba-8620-2d8bccdf2bfb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_af5a9855-7b76-4e2f-8e0a-f84f5270ea87" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_b0c4ab93-97e7-4b8e-acc9-bb2599224f30" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_af5a9855-7b76-4e2f-8e0a-f84f5270ea87" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_6ad64a00-eed4-418e-9346-f9d8b17f9dd3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_af5a9855-7b76-4e2f-8e0a-f84f5270ea87" xlink:to="loc_us-gaap_AwardTypeAxis_6ad64a00-eed4-418e-9346-f9d8b17f9dd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6ad64a00-eed4-418e-9346-f9d8b17f9dd3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_6ad64a00-eed4-418e-9346-f9d8b17f9dd3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_6ad64a00-eed4-418e-9346-f9d8b17f9dd3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8671d9c3-9ff2-441b-9b58-644d65586665" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_6ad64a00-eed4-418e-9346-f9d8b17f9dd3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8671d9c3-9ff2-441b-9b58-644d65586665" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_e83b806c-1c5e-4c30-a8ec-e611db3b075e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8671d9c3-9ff2-441b-9b58-644d65586665" xlink:to="loc_us-gaap_EmployeeStockOptionMember_e83b806c-1c5e-4c30-a8ec-e611db3b075e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_7799df6c-d987-4a68-b421-8420c7b161a0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_af5a9855-7b76-4e2f-8e0a-f84f5270ea87" xlink:to="loc_us-gaap_PlanNameAxis_7799df6c-d987-4a68-b421-8420c7b161a0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_7799df6c-d987-4a68-b421-8420c7b161a0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_7799df6c-d987-4a68-b421-8420c7b161a0" xlink:to="loc_us-gaap_PlanNameDomain_7799df6c-d987-4a68-b421-8420c7b161a0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_338555c5-f482-4e45-aca3-41c868105d13" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_7799df6c-d987-4a68-b421-8420c7b161a0" xlink:to="loc_us-gaap_PlanNameDomain_338555c5-f482-4e45-aca3-41c868105d13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ServicePeriodBasedApproachMember_e3f3cf71-813a-44a8-9d77-6fd4e6cc3a8d" xlink:href="acmr-20230630.xsd#acmr_ServicePeriodBasedApproachMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_338555c5-f482-4e45-aca3-41c868105d13" xlink:to="loc_acmr_ServicePeriodBasedApproachMember_e3f3cf71-813a-44a8-9d77-6fd4e6cc3a8d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_b205697b-9e87-4610-bc78-689cfdb809fb" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_af5a9855-7b76-4e2f-8e0a-f84f5270ea87" xlink:to="loc_srt_RangeAxis_b205697b-9e87-4610-bc78-689cfdb809fb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_b205697b-9e87-4610-bc78-689cfdb809fb_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_b205697b-9e87-4610-bc78-689cfdb809fb" xlink:to="loc_srt_RangeMember_b205697b-9e87-4610-bc78-689cfdb809fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_e87eaf81-a46e-437b-9858-29300fface87" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_b205697b-9e87-4610-bc78-689cfdb809fb" xlink:to="loc_srt_RangeMember_e87eaf81-a46e-437b-9858-29300fface87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_80b33758-c141-49bd-8bf0-333c40353539" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_e87eaf81-a46e-437b-9858-29300fface87" xlink:to="loc_srt_MinimumMember_80b33758-c141-49bd-8bf0-333c40353539" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_f79464e0-d5da-497a-bc2e-0e43e490bd36" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_e87eaf81-a46e-437b-9858-29300fface87" xlink:to="loc_srt_MaximumMember_f79464e0-d5da-497a-bc2e-0e43e490bd36" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/INCOMETAXESNarrativeDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#INCOMETAXESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/INCOMETAXESNarrativeDetails" xlink:type="extended" id="i29ee1f0355d145ac874d5d10b167ad00_INCOMETAXESNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_acmr_IncomeTaxesLineItems_bf99d79e-6e57-4aa5-850b-a9bd1656c17c" xlink:href="acmr-20230630.xsd#acmr_IncomeTaxesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_acmr_IncomeTaxesLineItems_bf99d79e-6e57-4aa5-850b-a9bd1656c17c" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_4e9237a1-d198-412d-b4eb-d9e9cf03bf3a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_4e9237a1-d198-412d-b4eb-d9e9cf03bf3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ForeignCorporateTaxRate_a45a3925-b961-4565-8b32-8c396aa1eb91" xlink:href="acmr-20230630.xsd#acmr_ForeignCorporateTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_acmr_ForeignCorporateTaxRate_a45a3925-b961-4565-8b32-8c396aa1eb91" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_bef78d67-e776-4d1a-a688-1263522cbf09" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_bef78d67-e776-4d1a-a688-1263522cbf09" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortizationPeriod_f01812f8-1790-4b92-be58-d8e80cbb3a1e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CapitalizedContractCostAmortizationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_CapitalizedContractCostAmortizationPeriod_f01812f8-1790-4b92-be58-d8e80cbb3a1e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_c67a9c3c-e7e4-42f1-b6ef-d0b4f961d48c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UnrecognizedTaxBenefits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_UnrecognizedTaxBenefits_c67a9c3c-e7e4-42f1-b6ef-d0b4f961d48c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_2f85a68d-d80b-414a-b671-e844f63f4a54" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_2f85a68d-d80b-414a-b671-e844f63f4a54" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_dceb1c38-ad04-45f2-aed4-02c24301614b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_dceb1c38-ad04-45f2-aed4-02c24301614b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NumberOfSubsidiaries_b8343910-a394-4fc9-bcd3-0bdc511e90d3" xlink:href="acmr-20230630.xsd#acmr_NumberOfSubsidiaries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_acmr_NumberOfSubsidiaries_b8343910-a394-4fc9-bcd3-0bdc511e90d3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_c06cb67e-d7c8-43db-a59e-e9871f7c84d7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_c06cb67e-d7c8-43db-a59e-e9871f7c84d7" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_EffectivePeriodOfPreferentialIncomeTaxRate_9ab6c2f8-788d-49df-8f4b-095ce6f890da" xlink:href="acmr-20230630.xsd#acmr_EffectivePeriodOfPreferentialIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAbstract_d63fa80d-8f9b-4dea-9803-1d8edb579eb1" xlink:to="loc_acmr_EffectivePeriodOfPreferentialIncomeTaxRate_9ab6c2f8-788d-49df-8f4b-095ce6f890da" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_IncomeTaxesTable_63763787-c5cb-49b2-8e4d-2455b4e8e34e" xlink:href="acmr-20230630.xsd#acmr_IncomeTaxesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_acmr_IncomeTaxesLineItems_bf99d79e-6e57-4aa5-850b-a9bd1656c17c" xlink:to="loc_acmr_IncomeTaxesTable_63763787-c5cb-49b2-8e4d-2455b4e8e34e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_1b60a72c-03f4-4682-8244-6db71f6c2700" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_IncomeTaxesTable_63763787-c5cb-49b2-8e4d-2455b4e8e34e" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_1b60a72c-03f4-4682-8244-6db71f6c2700" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_1b60a72c-03f4-4682-8244-6db71f6c2700_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_1b60a72c-03f4-4682-8244-6db71f6c2700" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_1b60a72c-03f4-4682-8244-6db71f6c2700_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_d8e1f550-17bd-4f44-a5ba-1e9e9e42a514" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_1b60a72c-03f4-4682-8244-6db71f6c2700" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_d8e1f550-17bd-4f44-a5ba-1e9e9e42a514" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_4018ec2a-2426-412a-b698-1f3ae8bd1a47" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_d8e1f550-17bd-4f44-a5ba-1e9e9e42a514" xlink:to="loc_us-gaap_ForeignCountryMember_4018ec2a-2426-412a-b698-1f3ae8bd1a47" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_e6e66048-58f7-4359-94a3-449caa73f9a3" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_IncomeTaxesTable_63763787-c5cb-49b2-8e4d-2455b4e8e34e" xlink:to="loc_srt_ConsolidatedEntitiesAxis_e6e66048-58f7-4359-94a3-449caa73f9a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_e6e66048-58f7-4359-94a3-449caa73f9a3_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_e6e66048-58f7-4359-94a3-449caa73f9a3" xlink:to="loc_srt_ConsolidatedEntitiesDomain_e6e66048-58f7-4359-94a3-449caa73f9a3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_0f118414-bb5c-4f87-8f4a-ed1344f75372" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_e6e66048-58f7-4359-94a3-449caa73f9a3" xlink:to="loc_srt_ConsolidatedEntitiesDomain_0f118414-bb5c-4f87-8f4a-ed1344f75372" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchShanghaiIncMember_07f32c6c-ef80-4c04-9774-fc0eabc78d00" xlink:href="acmr-20230630.xsd#acmr_ACMResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_0f118414-bb5c-4f87-8f4a-ed1344f75372" xlink:to="loc_acmr_ACMResearchShanghaiIncMember_07f32c6c-ef80-4c04-9774-fc0eabc78d00" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchWuxiIncMember_b657e0d4-2414-420f-a227-c4821984af5b" xlink:href="acmr-20230630.xsd#acmr_ACMResearchWuxiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_0f118414-bb5c-4f87-8f4a-ed1344f75372" xlink:to="loc_acmr_ACMResearchWuxiIncMember_b657e0d4-2414-420f-a227-c4821984af5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchBeijingIncMember_5992a301-b317-4b20-b48d-970bffb7e533" xlink:href="acmr-20230630.xsd#acmr_ACMResearchBeijingIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_0f118414-bb5c-4f87-8f4a-ed1344f75372" xlink:to="loc_acmr_ACMResearchBeijingIncMember_5992a301-b317-4b20-b48d-970bffb7e533" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShengweiResearchShanghaiIncMember_99006403-88c8-45ce-a583-11a5495bfb56" xlink:href="acmr-20230630.xsd#acmr_ShengweiResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_0f118414-bb5c-4f87-8f4a-ed1344f75372" xlink:to="loc_acmr_ShengweiResearchShanghaiIncMember_99006403-88c8-45ce-a583-11a5495bfb56" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_2f79cea8-e9a5-41d9-8739-02b2431c790a" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_acmr_IncomeTaxesTable_63763787-c5cb-49b2-8e4d-2455b4e8e34e" xlink:to="loc_srt_RangeAxis_2f79cea8-e9a5-41d9-8739-02b2431c790a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_2f79cea8-e9a5-41d9-8739-02b2431c790a_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_2f79cea8-e9a5-41d9-8739-02b2431c790a" xlink:to="loc_srt_RangeMember_2f79cea8-e9a5-41d9-8739-02b2431c790a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_8289bb56-9056-49e5-b9b6-4ba417314d68" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_2f79cea8-e9a5-41d9-8739-02b2431c790a" xlink:to="loc_srt_RangeMember_8289bb56-9056-49e5-b9b6-4ba417314d68" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_857a3385-abfe-4d67-84f8-e87971a323f2" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_8289bb56-9056-49e5-b9b6-4ba417314d68" xlink:to="loc_srt_MinimumMember_857a3385-abfe-4d67-84f8-e87971a323f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_a23a4a91-b76e-4060-a852-d7873863fed5" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_8289bb56-9056-49e5-b9b6-4ba417314d68" xlink:to="loc_srt_MaximumMember_a23a4a91-b76e-4060-a852-d7873863fed5" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SEGMENTINFORMATIONDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SEGMENTINFORMATIONDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SEGMENTINFORMATIONDetails" xlink:type="extended" id="i158e97e0b55345eda15cc909ebfd5aa6_SEGMENTINFORMATIONDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_aa504e72-fce7-4380-8b66-2e200561d938" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicAreasLongLivedAssetsAbstract_498e1531-b6e5-4918-bb69-ac037c6192c5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_GeographicAreasLongLivedAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_aa504e72-fce7-4380-8b66-2e200561d938" xlink:to="loc_us-gaap_GeographicAreasLongLivedAssetsAbstract_498e1531-b6e5-4918-bb69-ac037c6192c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncurrentAssets_6e66aeae-b5a3-4547-a556-47c5d4d5e437" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicAreasLongLivedAssetsAbstract_498e1531-b6e5-4918-bb69-ac037c6192c5" xlink:to="loc_us-gaap_NoncurrentAssets_6e66aeae-b5a3-4547-a556-47c5d4d5e437" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_73c335b7-2452-4170-ba38-f80175044b02" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_aa504e72-fce7-4380-8b66-2e200561d938" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_73c335b7-2452-4170-ba38-f80175044b02" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_df9dc4c2-39cd-495c-ad89-79502b434562" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_73c335b7-2452-4170-ba38-f80175044b02" xlink:to="loc_srt_StatementGeographicalAxis_df9dc4c2-39cd-495c-ad89-79502b434562" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_df9dc4c2-39cd-495c-ad89-79502b434562_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_df9dc4c2-39cd-495c-ad89-79502b434562" xlink:to="loc_srt_SegmentGeographicalDomain_df9dc4c2-39cd-495c-ad89-79502b434562_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_ef61dd3c-476b-4db2-b507-b37085fb3b47" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_df9dc4c2-39cd-495c-ad89-79502b434562" xlink:to="loc_srt_SegmentGeographicalDomain_ef61dd3c-476b-4db2-b507-b37085fb3b47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_8d84942b-23eb-4793-a6ae-f546e3f1ca68" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ef61dd3c-476b-4db2-b507-b37085fb3b47" xlink:to="loc_country_CN_8d84942b-23eb-4793-a6ae-f546e3f1ca68" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_KR_51ac4038-3951-430b-8540-9d04b9edb258" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_KR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ef61dd3c-476b-4db2-b507-b37085fb3b47" xlink:to="loc_country_KR_51ac4038-3951-430b-8540-9d04b9edb258" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_4b4ed778-1b3c-4175-9e0e-65b12d51a8af" xlink:href="https://xbrl.sec.gov/country/2023/country-2023.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ef61dd3c-476b-4db2-b507-b37085fb3b47" xlink:to="loc_country_US_4b4ed778-1b3c-4175-9e0e-65b12d51a8af" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/STATUTORYSURPLUSRESERVEDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#STATUTORYSURPLUSRESERVEDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/STATUTORYSURPLUSRESERVEDetails" xlink:type="extended" id="i76b2ad8b8eab4d35941b7fadde7dfe26_STATUTORYSURPLUSRESERVEDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatutoryAccountingPracticesLineItems_1bb3c2a0-0331-4c11-b092-0e70cdba629a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatutoryAccountingPracticesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficitAbstract_76d0c435-3ec6-44cb-9c67-bda98428a5db" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsAccumulatedDeficitAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatutoryAccountingPracticesLineItems_1bb3c2a0-0331-4c11-b092-0e70cdba629a" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficitAbstract_76d0c435-3ec6-44cb-9c67-bda98428a5db" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance_5ade3ae8-27d2-48ac-b103-e85362ff1628" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetainedEarningsAccumulatedDeficitAbstract_76d0c435-3ec6-44cb-9c67-bda98428a5db" xlink:to="loc_us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance_5ade3ae8-27d2-48ac-b103-e85362ff1628" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatutoryAccountingPracticesTable_81235569-6d57-4b21-af12-ea0fd131d3a4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatutoryAccountingPracticesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatutoryAccountingPracticesLineItems_1bb3c2a0-0331-4c11-b092-0e70cdba629a" xlink:to="loc_us-gaap_StatutoryAccountingPracticesTable_81235569-6d57-4b21-af12-ea0fd131d3a4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_9723090b-5010-445d-abcb-f1aa495154fc" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatutoryAccountingPracticesTable_81235569-6d57-4b21-af12-ea0fd131d3a4" xlink:to="loc_srt_ConsolidatedEntitiesAxis_9723090b-5010-445d-abcb-f1aa495154fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_9723090b-5010-445d-abcb-f1aa495154fc_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_9723090b-5010-445d-abcb-f1aa495154fc" xlink:to="loc_srt_ConsolidatedEntitiesDomain_9723090b-5010-445d-abcb-f1aa495154fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_8ed6a84b-c1f8-42c6-a9ce-8c2f34fb010c" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_9723090b-5010-445d-abcb-f1aa495154fc" xlink:to="loc_srt_ConsolidatedEntitiesDomain_8ed6a84b-c1f8-42c6-a9ce-8c2f34fb010c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ACMResearchShanghaiIncMember_4598e777-9146-4351-a75c-7100cec5cd7a" xlink:href="acmr-20230630.xsd#acmr_ACMResearchShanghaiIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_8ed6a84b-c1f8-42c6-a9ce-8c2f34fb010c" xlink:to="loc_acmr_ACMResearchShanghaiIncMember_4598e777-9146-4351-a75c-7100cec5cd7a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://acmrcsh.com/role/SUBSEQUENTEVENTSDetails" xlink:type="simple" xlink:href="acmr-20230630.xsd#SUBSEQUENTEVENTSDetails"/>
  <link:definitionLink xlink:role="http://acmrcsh.com/role/SUBSEQUENTEVENTSDetails" xlink:type="extended" id="i2f5d1105edb54272ac8e8202fd1afc2e_SUBSEQUENTEVENTSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_7ab57ff8-3059-47a9-83e9-de8350ad1cc0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_d71dc1ff-5ac0-4c30-b0a3-fae84bc2be17" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_7ab57ff8-3059-47a9-83e9-de8350ad1cc0" xlink:to="loc_us-gaap_LongTermDebt_d71dc1ff-5ac0-4c30-b0a3-fae84bc2be17" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_c0ee5150-30e0-4292-946f-be9a04ae2b2a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_7ab57ff8-3059-47a9-83e9-de8350ad1cc0" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_c0ee5150-30e0-4292-946f-be9a04ae2b2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_b9825b79-b383-4c38-96b3-63cdce056fb0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_7ab57ff8-3059-47a9-83e9-de8350ad1cc0" xlink:to="loc_us-gaap_SubsequentEventTable_b9825b79-b383-4c38-96b3-63cdce056fb0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_90930db6-bed7-475c-ad05-93e2aedb6a2b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_b9825b79-b383-4c38-96b3-63cdce056fb0" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_90930db6-bed7-475c-ad05-93e2aedb6a2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_90930db6-bed7-475c-ad05-93e2aedb6a2b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_90930db6-bed7-475c-ad05-93e2aedb6a2b" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_90930db6-bed7-475c-ad05-93e2aedb6a2b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_7b3de8d9-cc55-46c9-bc79-4a74e365ed0b" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_90930db6-bed7-475c-ad05-93e2aedb6a2b" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_7b3de8d9-cc55-46c9-bc79-4a74e365ed0b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_185473f4-b343-458b-bb2e-3ef9cbdc59fe" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_7b3de8d9-cc55-46c9-bc79-4a74e365ed0b" xlink:to="loc_us-gaap_SubsequentEventMember_185473f4-b343-458b-bb2e-3ef9cbdc59fe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_84e2b8ec-997e-4894-85b7-847017213e00" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_b9825b79-b383-4c38-96b3-63cdce056fb0" xlink:to="loc_us-gaap_DebtInstrumentAxis_84e2b8ec-997e-4894-85b7-847017213e00" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_84e2b8ec-997e-4894-85b7-847017213e00_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_84e2b8ec-997e-4894-85b7-847017213e00" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_84e2b8ec-997e-4894-85b7-847017213e00_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_332fa15c-2bc3-454b-8c4c-b290c9ddb0fc" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_84e2b8ec-997e-4894-85b7-847017213e00" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_332fa15c-2bc3-454b-8c4c-b290c9ddb0fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_LoanContractDueOnDecember212022Member_0f511130-1ba1-48ba-a29a-2ae5f9619b9c" xlink:href="acmr-20230630.xsd#acmr_LoanContractDueOnDecember212022Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_332fa15c-2bc3-454b-8c4c-b290c9ddb0fc" xlink:to="loc_acmr_LoanContractDueOnDecember212022Member_0f511130-1ba1-48ba-a29a-2ae5f9619b9c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_0187b134-0207-4d02-ba81-61bdd36d5edb" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_b9825b79-b383-4c38-96b3-63cdce056fb0" xlink:to="loc_us-gaap_VariableRateAxis_0187b134-0207-4d02-ba81-61bdd36d5edb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_0187b134-0207-4d02-ba81-61bdd36d5edb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_0187b134-0207-4d02-ba81-61bdd36d5edb" xlink:to="loc_us-gaap_VariableRateDomain_0187b134-0207-4d02-ba81-61bdd36d5edb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_4cec2c14-a4e0-42c3-bfa1-5655dc097073" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_0187b134-0207-4d02-ba81-61bdd36d5edb" xlink:to="loc_us-gaap_VariableRateDomain_4cec2c14-a4e0-42c3-bfa1-5655dc097073" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_NationalInterbankFundingCenterOneYearLoanMarketQuotationRateMember_ddf04d13-ca67-4f16-9377-8ca8c6dbb637" xlink:href="acmr-20230630.xsd#acmr_NationalInterbankFundingCenterOneYearLoanMarketQuotationRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_4cec2c14-a4e0-42c3-bfa1-5655dc097073" xlink:to="loc_acmr_NationalInterbankFundingCenterOneYearLoanMarketQuotationRateMember_ddf04d13-ca67-4f16-9377-8ca8c6dbb637" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/AwardTypeOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2023/ecd-2023.xsd#AwardTypeOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/AwardTypeOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember_c4557227-d79d-46c4-b00b-e7d341a98db6" xlink:href="acmr-20230630.xsd#acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_acmr_ShareBasedPaymentArrangementNonEmployeeStockOptionMember_c4557227-d79d-46c4-b00b-e7d341a98db6" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2023/ecd-2023.xsd#IndividualsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllIndividualsMember" xlink:href="https://xbrl.sec.gov/ecd/2023/ecd-2023.xsd#ecd_AllIndividualsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_FupingChenMember_0314bbf2-fc68-477c-87b9-fc15c2ceed3a" xlink:href="acmr-20230630.xsd#acmr_FupingChenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_acmr_FupingChenMember_0314bbf2-fc68-477c-87b9-fc15c2ceed3a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_HaipingDunMember_f596c219-d768-4b7d-ba04-663ba04bd417" xlink:href="acmr-20230630.xsd#acmr_HaipingDunMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_acmr_HaipingDunMember_f596c219-d768-4b7d-ba04-663ba04bd417" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_acmr_DavidWangMember_ee6c79fa-bfd0-435a-9639-80b477a6f116" xlink:href="acmr-20230630.xsd#acmr_DavidWangMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_acmr_DavidWangMember_ee6c79fa-bfd0-435a-9639-80b477a6f116" xlink:type="arc" order="4"/>
  </link:definitionLink>
</link:linkbase>
