<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-11-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001338065</issuerCik>
        <issuerName>DCP Midstream, LP</issuerName>
        <issuerTradingSymbol>DCP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001119811</rptOwnerCik>
            <rptOwnerName>DCP MIDSTREAM, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>370 17TH STREET, SUITE 2500</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DENVER</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Units representing limited partner interests</value>
            </securityTitle>
            <transactionDate>
                <value>2019-11-06</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>65000000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>66887618</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Units representing limited partner interests</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50874908</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On November 6, 2019, in connection with the transactions contemplated by the Equity Restructuring Agreement dated November 6, 2019, by and between DCP Midstream GP, LP (the &quot;General Partner&quot;) and DCP Midstream, LP (the &quot;Partnership&quot;), the General Partner, which is an indirect wholly owned subsidiary of DCP Midstream, LLC (&quot;Midstream&quot;), acquired from the Partnership 65,000,000 common units representing limited partner interests in the Partnership (the &quot;Common Units&quot;) in exchange for the conversion of the General Partner's general partner interest in the Partnership into a non-economic general partner interest and the cancellation of all of the outstanding general partner units and incentive distribution rights of the Partnership, all of which were held by the General Partner.</footnote>
        <footnote id="F2">The Common Units are held of record by the General Partner. Midstream directly owns DCP Midstream GP, LLC, the general partner of the General Partner, and all of the limited partner interests in the General Partner. Accordingly, Midstream may be deemed to indirectly own the securities of the Partnership directly held by the General Partner, but disclaims beneficial ownership except to the extent of its pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Michael S. Richards, Vice President, Deputy General Counsel &amp; Corporate Secretary</signatureName>
        <signatureDate>2019-11-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
