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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-12-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001364250</issuerCik>
        <issuerName>Douglas Emmett Inc</issuerName>
        <issuerTradingSymbol>DEI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001486426</rptOwnerCik>
            <rptOwnerName>Feinberg David T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1299 OCEAN AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1000</rptOwnerStreet2>
            <rptOwnerCity>SANTA MONICA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90401</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Long Term Incentive Plan Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.00</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-12-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>7621</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2021-03-31</value>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2030-12-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7621</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7621</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Long term incentive plan units (&quot;LTIP Units&quot;) in Douglas Emmett Properties, LP, a DE limited partnership (the &quot;Operating Partnership&quot;) granted
pursuant to the 2016 Omnibus Stock Incentive Plan of Douglas Emmett, Inc. (&quot;Issuer&quot;). Issuer is the sole stockholder of the general partner of
the Operating Partnership. Upon vesting, each LTIP Unit can be converted into one partnership common unit (&quot;OP Unit&quot;) of the Operating
Partnership, which is ultimately exchangeable into common stock of Issuer, only, if applicable, after achievement of a specified percentage increase in Gross
Asset Values of the assets of the Operating Partnership. LTIP Units not converted into OP Units within 10 years of the grant date will be
forfeited. Upon the occurrence of certain events, OP Units are redeemable by the holder, without consideration, for an equivalent number of
shares of Issuer's common stock or for the cash value of such shares, at Issuer's election.</footnote>
        <footnote id="F2">LTIP Units granted as part of Reporting Person's annual compensation for service as a director of Issuer.</footnote>
        <footnote id="F3">LTIP Units vest in one-quarter equal installments on March 31, 2021, June 30, 2021, September 30, 2021, and December 31, 2021.</footnote>
        <footnote id="F4">Derivative securities owned by the Reporting Person include the LTIP Units reported herein, an additional 6,501 fully vested LTIP Units previously granted pursuant to Issuer's 2016 Omnibus Stock Incentive Plan, and 49,890 OP Units.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ben D. Orlanski by PA for David T. Feinberg</signatureName>
        <signatureDate>2021-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
