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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2019-02-26</periodOfReport>

    <dateOfOriginalSubmission>2019-02-28</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001099219</issuerCik>
        <issuerName>METLIFE INC</issuerName>
        <issuerTradingSymbol>MET</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001585015</rptOwnerCik>
            <rptOwnerName>Lee Esther</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>METLIFE, INC., 200 PARK AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10166</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP &amp; Chief Marketing Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-02-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>323</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>44.65</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>26190</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The Reporting Person earned 12,776 shares from 2016-2018 Performance Shares pursuant to the MetLife, Inc. 2015 Stock and Incentive Compensation Plan.  She deferred those shares under the MetLife Leadership Deferred Compensation Plan, which allows eligible employees to defer receipt of such stock for a specific period of time.  The Company withheld 323 shares to satisfy withholding for FICA and Medicare taxes.  These withheld shares were inadvertently omitted from the original, timely February 28, 2019 report of the Reporting Person's deferred share acquisition.</footnote>
        <footnote id="F2">As a result of the inadvertent omission described in footnote (1), the amount of securities beneficially owned by the Reporting Person was incorrectly stated on the report filed on February 28, 2019.  The amount in Table I box 5 of this report is the amount of ownership immediately following the transaction reported on this form. By this note, this report also corrects the amount of securities beneficially owned following each of the reported transactions in box 5 of Table I of the Reporting Person's report filed on March 5, 2019 to 28,619; 27,690; 29,468; 28,788; 30,107; and 29,602, respectively.</footnote>
    </footnotes>

    <remarks>The Reporting Person's Section 16 disclosure will round Deferred Shares and Deferred Share Equivalents to the nearest whole number.</remarks>

    <ownerSignature>
        <signatureName>/s/ Mark A. Schuman, authorized signer</signatureName>
        <signatureDate>2019-04-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
