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    <periodOfReport>2021-01-15</periodOfReport>

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    <issuer>
        <issuerCik>0001287865</issuerCik>
        <issuerName>MEDICAL PROPERTIES TRUST INC</issuerName>
        <issuerTradingSymbol>MPW</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001331608</rptOwnerCik>
            <rptOwnerName>Aldag Edward K JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1000 URBAN CENTER DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 501</rptOwnerStreet2>
            <rptOwnerCity>BIRMINGHAM</rptOwnerCity>
            <rptOwnerState>AL</rptOwnerState>
            <rptOwnerZipCode>35242</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman, President &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <underlyingSecurityTitle>
                    <value>Common stock, par value $0.001</value>
                </underlyingSecurityTitle>
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    <footnotes>
        <footnote id="F1">Shares vest ratably at the beginning of each of the 12 calendar quarters beginning April 1, 2021.</footnote>
        <footnote id="F2">Shares will be earned based on the achievement of specific performance thresholds pertaining to the Company's per share funds from operations, EBITDA, and acquisitions, as defined and set by our compensation committee, over the period from January 1, 2021 through December 31, 2023, with the opportunity to earn up to one third of the award for 2021 performance against the specified measures. The actual number of shares to be issued will vary depending upon the achievement of specific performance thresholds.</footnote>
        <footnote id="F3">Represents additional shares earned under the 2020 performance award based on the Company's actual performance as compared to the performance hurdles defined in the award agreement along with shares earned pursuant to the modifier provisions in the award, which allowed for more shares to be earned based on the Company's total return to shareholders and how the Company's relative total return to shareholders compared to the SNL Healthcare REIT Index. The shares vested on January 1, 2021.</footnote>
        <footnote id="F4">Represents shares earned under the 2018 performance award equal to approximately one third of the target number of shares granted.</footnote>
        <footnote id="F5">Represents additional shares earned under the 2018 performance award based on the Company's actual performance as compared to the performance hurdles defined in the award agreement along with shares earned pursuant to the modifier provisions in the award, which allowed for more shares to be earned based on how the Company's relative total return to shareholders compared to the SNL Healthcare REIT Index. The shares vested on January 1, 2021.</footnote>
        <footnote id="F6">The shares vested on January 1, 2021.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Emily R. Sawyer, by power of attorney</signatureName>
        <signatureDate>2021-01-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
