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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-12-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001630472</issuerCik>
        <issuerName>TPG RE Finance Trust, Inc.</issuerName>
        <issuerTradingSymbol>TRTX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001696998</rptOwnerCik>
            <rptOwnerName>Coleman Matthew</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O TPG RE FINANCE TRUST, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>888 SEVENTH AVENUE, 35TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10106</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-12-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5144</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5144</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9447</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Explanation of Responses</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On December 13, 2017, Mr. Matthew Coleman acquired shares of Class A common stock (&quot;Class A Common Stock&quot;) of TPG RE Finance Trust, Inc. (the &quot;Issuer&quot;) from TPG RE Finance Trust Management, L.P. (the &quot;Manager&quot;), the Issuer's external manager, pursuant to a grant made by the Manager to Mr. Coleman in accordance with the terms of a compensatory plan adopted by the Manager.  The Manager acquired the shares of Class A Common Stock prior to the completion of the Issuer's initial public offering and granted the shares to Mr. Coleman as compensation for services Mr. Coleman provided to the Issuer.  The shares of Class A Common Stock are subject to the terms of a lock-up agreement entered into by Mr. Coleman in connection with the Issuer's initial public offering.</footnote>
        <footnote id="F2">The shares of Class A Common Stock awarded to Mr. Coleman will vest ratably in four annual installments beginning on June 30, 2018.  Upon vesting, the shares of Class A Common Stock will be delivered to Mr. Coleman.</footnote>
        <footnote id="F3">TPG RE Finance Trust Equity, L.P. (&quot;TPG RE Finance Trust Equity&quot;) directly holds 926,951 shares of Class A Common Stock, including 4,303 shares of Class A Common Stock indirectly beneficially owned by Mr. Coleman (through his indirect limited partnership interest in TPG RE Finance Trust Equity).</footnote>
        <footnote id="F4">Pursuant to the Articles of Amendment and Restatement of the Issuer, each share of Class A Common Stock is convertible at any time or from time to time, at the option of the holder, for one share of common stock of the Issuer.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Matthew Coleman</signatureName>
        <signatureDate>2017-12-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
