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

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2022 Workiva-->
<!--r:fa127fc1-e7dc-46e0-91ef-ce4fd492e68f,g:8b4fc49e-6ac4-4154-b029-fb24cccd7551-->
<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://www.anaptysbio.com/role/CoverPage" xlink:type="simple" xlink:href="anab-20220307.xsd#CoverPage"/>
  <link:definitionLink xlink:role="http://www.anaptysbio.com/role/CoverPage" xlink:type="extended" id="idee08d51a54b4ee2878ce01dcee64e0b_CoverPage">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_bee03c68-75ec-4945-9652-80337462eb45" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_ce21716a-2d9b-4946-86db-f84f2a0872d6" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_bee03c68-75ec-4945-9652-80337462eb45" xlink:to="loc_dei_DocumentType_ce21716a-2d9b-4946-86db-f84f2a0872d6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_0c321496-9cbd-4364-a379-6095bf897cec" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_bee03c68-75ec-4945-9652-80337462eb45" xlink:to="loc_dei_DocumentInformationTable_0c321496-9cbd-4364-a379-6095bf897cec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationDocumentAxis_72e9d696-c344-4221-9e37-1b5633c00e9f" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentInformationDocumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_0c321496-9cbd-4364-a379-6095bf897cec" xlink:to="loc_dei_DocumentInformationDocumentAxis_72e9d696-c344-4221-9e37-1b5633c00e9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentDomain_72e9d696-c344-4221-9e37-1b5633c00e9f_default" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_DocumentInformationDocumentAxis_72e9d696-c344-4221-9e37-1b5633c00e9f" xlink:to="loc_dei_DocumentDomain_72e9d696-c344-4221-9e37-1b5633c00e9f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentDomain_4d7b0acf-e985-4c2d-8111-8f67f4a8617f" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_DocumentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_DocumentInformationDocumentAxis_72e9d696-c344-4221-9e37-1b5633c00e9f" xlink:to="loc_dei_DocumentDomain_4d7b0acf-e985-4c2d-8111-8f67f4a8617f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_87f8b9c4-636d-44b2-9abb-6632363496ee" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:to="loc_dei_EntityAddressAddressLine1_87f8b9c4-636d-44b2-9abb-6632363496ee" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_39a1bc44-b899-4451-8dce-772ec0366216" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressAddressLine2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:to="loc_dei_EntityAddressAddressLine2_39a1bc44-b899-4451-8dce-772ec0366216" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_edbe53ec-b5aa-4fe8-b513-47f72fa5323f" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:to="loc_dei_EntityAddressCityOrTown_edbe53ec-b5aa-4fe8-b513-47f72fa5323f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_40640db5-0969-44d5-91fe-103146c02b8f" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:to="loc_dei_EntityAddressStateOrProvince_40640db5-0969-44d5-91fe-103146c02b8f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_769ab36b-84eb-49f8-bbac-47b47ab48f5b" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:to="loc_dei_EntityAddressPostalZipCode_769ab36b-84eb-49f8-bbac-47b47ab48f5b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressesTable_ad854d64-8239-4a5a-bb4f-c9eba1dc807c" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityAddressesLineItems_0e710fba-3a78-4b32-b2a8-7a1fc3100cde" xlink:to="loc_dei_EntityAddressesTable_ad854d64-8239-4a5a-bb4f-c9eba1dc807c" xlink:type="arc" order="2" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressesAddressTypeAxis_bf218153-b32f-46ab-8e0b-ef5b5a94ac64" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_EntityAddressesAddressTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntityAddressesTable_ad854d64-8239-4a5a-bb4f-c9eba1dc807c" xlink:to="loc_dei_EntityAddressesAddressTypeAxis_bf218153-b32f-46ab-8e0b-ef5b5a94ac64" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AddressTypeDomain_bf218153-b32f-46ab-8e0b-ef5b5a94ac64_default" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_AddressTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_EntityAddressesAddressTypeAxis_bf218153-b32f-46ab-8e0b-ef5b5a94ac64" xlink:to="loc_dei_AddressTypeDomain_bf218153-b32f-46ab-8e0b-ef5b5a94ac64_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AddressTypeDomain_b1e5a9cc-a46e-4b9a-893b-0d23255d3eca" xlink:href="https://xbrl.sec.gov/dei/2021q4/dei-2021q4.xsd#dei_AddressTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_EntityAddressesAddressTypeAxis_bf218153-b32f-46ab-8e0b-ef5b5a94ac64" xlink:to="loc_dei_AddressTypeDomain_b1e5a9cc-a46e-4b9a-893b-0d23255d3eca" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
