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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-07-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000908311</issuerCik>
        <issuerName>CIM Commercial Trust Corp</issuerName>
        <issuerTradingSymbol>CMCT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000904290</rptOwnerCik>
            <rptOwnerName>RESSLER RICHARD S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4700 WILSHIRE BLVD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Series A Preferred Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2020-07-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>106518</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>106518</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote (2)</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">CIM Service Provider (&quot;CIM Service Provider&quot;), a wholly owned subsidiary of CIM Group, LLC, received 11,273 shares of Series A Preferred Stock from the Issuer as payment for the fee owed by the Issuer to CIM Service Provider in respect of the first fiscal quarter of 2020 pursuant to the master services agreement between CIM Service Provider and the Issuer.  CIM Capital, LLC (&quot;CIM Capital&quot;), a wholly owned subsidiary of CIM Group, LLC, received 95,245 shares of Series A Preferred Stock from the Issuer as payment for the obligation of CIM Urban Partners, L.P. (&quot;CIM Urban&quot;), a wholly-owned indirect subsidiary of the Issuer, to pay CIM Capital a management fee in respect of the second fiscal quarter of 2020 pursuant to the investment management agreement between CIM Capital and CIM Urban.</footnote>
        <footnote id="F2">CIM Group, LLC is the sole equity member of CIM Service Provider and CIM Capital, respectively.  The reporting person, Avraham Shemesh and Shaul Kuba may be deemed to beneficially own all of the shares of Series A Preferred Stock acquired from CIM Service Provider and CIM Capital because of their positions with CIM Group, LLC.  The reporting person disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein, and the inclusion of such shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ David Thompson, attorney in fact</signatureName>
        <signatureDate>2020-07-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
