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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-09-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001466225</issuerCik>
        <issuerName>Resource Real Estate Opportunity REIT, Inc.</issuerName>
        <issuerTradingSymbol>NONE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001230064</rptOwnerCik>
            <rptOwnerName>FELDMAN ALAN F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1845 WALNUT STREET, 17TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PHILADELPHIA</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>See Remarks</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-09-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>250912</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>259523.154</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">An initial grant (the &quot;Equity Grant&quot;) of restricted stock of Resource Real Estate Opportunity REIT, Inc., a Maryland corporation (the &quot;Issuer&quot;) was granted to the reporting person as equity incentive compensation pursuant to the Issuer's 2020 Long-Term Incentive Plan (the &quot;Long-Term Incentive Plan&quot;). The Equity Grant vests in two tranches - 40% of the total number of shares will vest upon the consummation of the Issuer's merger with Resource Real Estate Opportunity REIT II, Inc. and 60% of the total number of shares will vest upon a liquidity event so long as the reporting person remains continuously employed through such vesting date. Unless sooner terminated in accordance with its terms, the Equity Grant will terminate on the date that is ten (10) years following the date on which the Long-Term Incentive Plan was adopted by the Issuer's board of directors.</footnote>
    </footnotes>

    <remarks>Chairman of the Board, Chief Executive Officer, President and Director</remarks>

    <ownerSignature>
        <signatureName>/s/ Michele Weisbaum, Attorney-in-Fact_</signatureName>
        <signatureDate>2020-09-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
