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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:01a17e75-f582-7d69-ae5a-6609b2c5b7e4,g:6da177ba-f376-434b-86eb-e8401750e2fa-->
<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" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.oncolyticsbiotech.com/role/Cover" xlink:type="simple" xlink:href="oncy-20261104.xsd#Cover"/>
  <link:presentationLink xlink:role="http://www.oncolyticsbiotech.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CoverAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_01a17e75-f582-730a-b2b7-53d53142bf37" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentType"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_DocumentType_01a17e75-f582-730a-b2b7-53d53142bf37" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_01a17e75-f582-76e0-9d88-6fa066f25b06" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_DocumentPeriodEndDate_01a17e75-f582-76e0-9d88-6fa066f25b06" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_01a17e75-f582-7e45-ba0d-119f245dd23b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName"/>
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityRegistrantName_01a17e75-f582-7e45-ba0d-119f245dd23b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_01a17e75-f582-7c41-af69-681982e57352" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityIncorporationStateCountryCode_01a17e75-f582-7c41-af69-681982e57352" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_01a17e75-f582-7afa-a1f6-bbd287019cec" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber"/>
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityFileNumber_01a17e75-f582-7afa-a1f6-bbd287019cec" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_01a17e75-f582-7222-b942-a702b791df2b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1"/>
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityAddressAddressLine1_01a17e75-f582-7222-b942-a702b791df2b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_01a17e75-f582-7346-9663-00c5398400ea" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine2"/>
    <link:presentationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityAddressAddressLine2_01a17e75-f582-7346-9663-00c5398400ea" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_01a17e75-f582-7802-95d4-143a71c359c2" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown"/>
    <link:presentationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityAddressCityOrTown_01a17e75-f582-7802-95d4-143a71c359c2" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_01a17e75-f582-7165-91f7-c17b735b909a" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressStateOrProvince"/>
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityAddressStateOrProvince_01a17e75-f582-7165-91f7-c17b735b909a" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_01a17e75-f582-765a-a759-db2f20b17dc0" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode"/>
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityAddressPostalZipCode_01a17e75-f582-765a-a759-db2f20b17dc0" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_01a17e75-f582-7ef9-817c-bcf5f8068ca5" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode"/>
    <link:presentationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_CityAreaCode_01a17e75-f582-7ef9-817c-bcf5f8068ca5" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_01a17e75-f582-7836-beb4-89b3a7e69b2c" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber"/>
    <link:presentationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_LocalPhoneNumber_01a17e75-f582-7836-beb4-89b3a7e69b2c" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_01a17e75-f582-7809-b26e-9d954aa86f17" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_WrittenCommunications"/>
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_WrittenCommunications_01a17e75-f582-7809-b26e-9d954aa86f17" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_01a17e75-f582-75b0-b6bc-eb3cf33e4b58" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SolicitingMaterial"/>
    <link:presentationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_SolicitingMaterial_01a17e75-f582-75b0-b6bc-eb3cf33e4b58" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_01a17e75-f582-7378-85fc-6994043ca86d" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementTenderOffer"/>
    <link:presentationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_PreCommencementTenderOffer_01a17e75-f582-7378-85fc-6994043ca86d" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_01a17e75-f582-759c-a85f-726c4a766cc6" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_01a17e75-f582-759c-a85f-726c4a766cc6" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_01a17e75-f582-709d-a4c7-0841d29016bc" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12bTitle"/>
    <link:presentationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_Security12bTitle_01a17e75-f582-709d-a4c7-0841d29016bc" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_01a17e75-f582-7a92-91e2-dc6c1ff2ca73" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_TradingSymbol"/>
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_TradingSymbol_01a17e75-f582-7a92-91e2-dc6c1ff2ca73" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_01a17e75-f582-7c54-aa2a-1fa5eb71d33f" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityExchangeName"/>
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_SecurityExchangeName_01a17e75-f582-7c54-aa2a-1fa5eb71d33f" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_01a17e75-f582-719e-a424-2120c013dcd6" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:presentationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityEmergingGrowthCompany_01a17e75-f582-719e-a424-2120c013dcd6" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_01a17e75-f582-7fed-9177-4643e3f0a22b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentFlag"/>
    <link:presentationArc order="21" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_AmendmentFlag_01a17e75-f582-7fed-9177-4643e3f0a22b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_01a17e75-f582-7ea8-9f3c-1506bfa2879b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCentralIndexKey"/>
    <link:presentationArc order="22" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_01a17e75-f582-7066-84e4-cf8fb477a7d4" xlink:to="loc_dei_EntityCentralIndexKey_01a17e75-f582-7ea8-9f3c-1506bfa2879b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
  </link:presentationLink>
</link:linkbase>
