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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-03-02</periodOfReport>

    <issuer>
        <issuerCik>0000789570</issuerCik>
        <issuerName>MGM Resorts International</issuerName>
        <issuerTradingSymbol>MGM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184914</rptOwnerCik>
            <rptOwnerName>D'ARRIGO DANIEL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3600 LAS VEGAS BLVD. SOUTH</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89109</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>EXECUTIVE VICE PRESIDENT &amp; CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>MIP Performance Share Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2015-03-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>21196</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2018-03-02</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-03-02</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock $.01 Par Value ND</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>21196</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>21196</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Management Incentive Plan Performance Share Units (&quot;MIP PSUs&quot;) granted under the MGM Resorts International (&quot;MGM Resorts&quot;) Amended and Restated 2005 Omnibus Incentive Plan and the Second Amended and Restated Annual Performance-Based Incentive Plan for Executive Officers, pursuant to MGM Resorts' Form of Performance Share Units Agreement (Bonus Payout). Each MIP PSU represents the right to receive between 0 and 1.6 shares of MGM Resorts common stock depending upon the performance of the common stock from the grant date to the date that is three years after the grant date (the &quot;Performance End Date&quot;), relative to a target price of $25.91 (the &quot;Target Price&quot;). The Target Price is equal to 125% of the average closing price of MGM Resorts common stock over the 60-calendar-day period ending on the grant date. If the ending average stock price is less than 60% of the Target Price (the &quot;Minimum Price&quot;), then no shares will be issued on the Performance End Date. If the ending average stock price is equal to or greater than 160% of the Target Price (the &quot;Maximum Price&quot;), then 1.6 shares will be issued on the Performance End Date per MIP PSU. If the ending average stock price is between the Minimum Price and the Maximum Price, then a number of shares will be issued on the Performance End Date per MIP PSU equal to the ending average stock price divided by the Target Price. For this purpose, the ending average stock price is the average closing price of MGM Resorts common stock over the 60-calendar-day period ending on the Performance End Date. MIP PSUs shall not be subject to forfeiture in the event that the participant's employment terminates for any reason.</footnote>
        <footnote id="F2">MIP PSUs become payable following the earlier of (i) a change in control or (ii) the Performance End Date of March 2, 2018.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Andrew Hagopian III, Attorney-In-Fact</signatureName>
        <signatureDate>2015-03-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
