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

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2021 Workiva-->
<!--r:520a69a6-9188-4e53-b066-f7f911d78a59,g:8f037ff4-88f5-4da8-bbc4-a6aa1f781a57-->
<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.portlandgeneral.com/role/Cover" xlink:type="simple" xlink:href="por-20210219.xsd#Cover"/>
  <link:presentationLink xlink:role="http://www.portlandgeneral.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_CoverAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_1be8233b-ca13-49c3-8130-759ebec39cab" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_DocumentType"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_DocumentType_1be8233b-ca13-49c3-8130-759ebec39cab" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_d197a609-2a09-4050-90b4-727fad6e7873" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_DocumentPeriodEndDate"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_DocumentPeriodEndDate_d197a609-2a09-4050-90b4-727fad6e7873" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_edf45616-db9f-46ee-b447-17573b62188e" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityRegistrantName"/>
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityRegistrantName_edf45616-db9f-46ee-b447-17573b62188e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_cb9347b7-785d-4e25-b4a9-77ba6f5b3aeb" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityIncorporationStateCountryCode_cb9347b7-785d-4e25-b4a9-77ba6f5b3aeb" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_6284bcb9-2c89-4444-92d9-b3b4b7fde86b" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityFileNumber"/>
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityFileNumber_6284bcb9-2c89-4444-92d9-b3b4b7fde86b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_aaec429c-e57c-42a4-96da-fec09a0b6771" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityTaxIdentificationNumber_aaec429c-e57c-42a4-96da-fec09a0b6771" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_278a95ed-174f-40a0-b8db-93860b58213e" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityAddressAddressLine1"/>
    <link:presentationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityAddressAddressLine1_278a95ed-174f-40a0-b8db-93860b58213e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_e2ff9803-68fe-4367-bd6b-8a4bf9ec74a7" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityAddressCityOrTown"/>
    <link:presentationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityAddressCityOrTown_e2ff9803-68fe-4367-bd6b-8a4bf9ec74a7" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_08b60fb9-0ec1-4c1d-8741-6daf43eac74f" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityAddressStateOrProvince"/>
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityAddressStateOrProvince_08b60fb9-0ec1-4c1d-8741-6daf43eac74f" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_3dda5be1-72f4-4cd1-857f-e3f3ffa75b5e" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityAddressPostalZipCode"/>
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityAddressPostalZipCode_3dda5be1-72f4-4cd1-857f-e3f3ffa75b5e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_145e37d7-e0e9-4eb4-837e-e72f43ed4a52" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_CityAreaCode"/>
    <link:presentationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_CityAreaCode_145e37d7-e0e9-4eb4-837e-e72f43ed4a52" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_8c866882-bb3b-4377-9125-7e2354043ce1" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_LocalPhoneNumber"/>
    <link:presentationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_LocalPhoneNumber_8c866882-bb3b-4377-9125-7e2354043ce1" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_9442008f-29ef-4b3f-ae37-061ab2ee0388" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_WrittenCommunications"/>
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_WrittenCommunications_9442008f-29ef-4b3f-ae37-061ab2ee0388" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_3c39e113-542c-4e2c-8e7e-d8d72ed3fec5" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_SolicitingMaterial"/>
    <link:presentationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_SolicitingMaterial_3c39e113-542c-4e2c-8e7e-d8d72ed3fec5" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_84be6348-3059-48c1-b0ac-2edf7b02bcd9" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_PreCommencementTenderOffer"/>
    <link:presentationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_PreCommencementTenderOffer_84be6348-3059-48c1-b0ac-2edf7b02bcd9" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_9ecdca48-f747-41fa-8b3b-7927ada57392" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_9ecdca48-f747-41fa-8b3b-7927ada57392" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_8de68573-6398-4795-9b42-ab09bb3ea9e3" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:presentationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityEmergingGrowthCompany_8de68573-6398-4795-9b42-ab09bb3ea9e3" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_bc9116e1-e379-425d-9abc-47faff9f6ee9" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_AmendmentFlag"/>
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_AmendmentFlag_bc9116e1-e379-425d-9abc-47faff9f6ee9" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_72c650fd-1ff6-4e7e-aba2-aa50243a9289" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityCentralIndexKey"/>
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_dei_EntityCentralIndexKey_72c650fd-1ff6-4e7e-aba2-aa50243a9289" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_4db2555d-f031-44a3-b58a-ff65c6bcb154" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementTable"/>
    <link:presentationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_d984f211-1dcf-44c1-95be-b7669994def9" xlink:to="loc_us-gaap_StatementTable_4db2555d-f031-44a3-b58a-ff65c6bcb154" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_58d8563c-513a-4c62-859a-fd327f4fc476" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_4db2555d-f031-44a3-b58a-ff65c6bcb154" xlink:to="loc_us-gaap_StatementClassOfStockAxis_58d8563c-513a-4c62-859a-fd327f4fc476" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_9e74a710-d875-4fa4-8bef-e6b0f99de652" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfStockDomain"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementClassOfStockAxis_58d8563c-513a-4c62-859a-fd327f4fc476" xlink:to="loc_us-gaap_ClassOfStockDomain_9e74a710-d875-4fa4-8bef-e6b0f99de652" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_954dc816-75f8-48b8-bd81-a664a533f2f1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockMember"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_9e74a710-d875-4fa4-8bef-e6b0f99de652" xlink:to="loc_us-gaap_CommonStockMember_954dc816-75f8-48b8-bd81-a664a533f2f1" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_9b158f3c-9738-4110-a62c-a3a02e51765b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MediumTermNotesMember"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_9e74a710-d875-4fa4-8bef-e6b0f99de652" xlink:to="loc_us-gaap_MediumTermNotesMember_9b158f3c-9738-4110-a62c-a3a02e51765b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_f6440354-92ba-4c81-8fc4-2721056cd5f2" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementLineItems"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_4db2555d-f031-44a3-b58a-ff65c6bcb154" xlink:to="loc_us-gaap_StatementLineItems_f6440354-92ba-4c81-8fc4-2721056cd5f2" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_6e5db7be-5a5e-44cc-9b15-6d9997ca49fb" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_Security12bTitle"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_f6440354-92ba-4c81-8fc4-2721056cd5f2" xlink:to="loc_dei_Security12bTitle_6e5db7be-5a5e-44cc-9b15-6d9997ca49fb" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_59271ba8-01a3-479c-877a-cd31b66d04eb" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_TradingSymbol"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_f6440354-92ba-4c81-8fc4-2721056cd5f2" xlink:to="loc_dei_TradingSymbol_59271ba8-01a3-479c-877a-cd31b66d04eb" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_d0543225-3545-439a-949a-66cbc5b4598e" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_SecurityExchangeName"/>
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_f6440354-92ba-4c81-8fc4-2721056cd5f2" xlink:to="loc_dei_SecurityExchangeName_d0543225-3545-439a-949a-66cbc5b4598e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
  </link:presentationLink>
</link:linkbase>
