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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2019-05-01</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001756262</issuerCik>
        <issuerName>TransMedics Group, Inc.</issuerName>
        <issuerTradingSymbol>TMDX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001774274</rptOwnerCik>
            <rptOwnerName>Gordon Stephen</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O TRANSMEDICS GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>200 MINUTEMAN ROAD</rptOwnerStreet2>
            <rptOwnerCity>ANDOVER</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01810</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>28571</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.67</value>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2025-04-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>57142</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.21</value>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-06-22</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>40728</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">As of the date of this Form 3, the Common Stock reported herein is common stock of TransMedics, Inc.  Immediately prior to the closing of the Issuer's initial public offering, pursuant to the terms of the Agreement and Plan of Merger and Reorganization by and among the Issuer, TransMedics, Inc. and TMDX, Inc., dated April 15, 2019 (the &quot;Merger Agreement&quot;) such common stock of TransMedics, Inc. will be converted into shares of common stock of the Issuer on a 3.5-for-one basis (the &quot;Common Stock Conversion&quot;). The number of shares in Column 2 reflects the Reporting Person's holdings following the Common Stock Conversion.</footnote>
        <footnote id="F2">The option is fully vested.</footnote>
        <footnote id="F3">As of the date of this Form 3, the Stock Options reported herein are options to purchase common stock of TransMedics, Inc.  Immediately prior to the closing of the Issuer's initial public offering, pursuant to the terms of the Merger Agreement, each outstanding option to purchase shares of common stock of TransMedics, Inc. will be converted into an outstanding option to purchase shares of common stock of the Issuer adjusted on a 3.5-for-one basis, with a corresponding adjustment to the exercise price.  The number of shares in Column 3 reflects the Reporting Person's holdings following such conversion and the exercise price in Column 4 reflects the exercise price following such conversion.</footnote>
        <footnote id="F4">The option vests at a rate of 2.0833% of the total number shares each month until the option is fully vested on the fourth anniversary of the vesting commencement date, June 22, 2017.</footnote>
    </footnotes>

    <remarks>Exhibit List: Exhibit 24 - Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>/s/ Stephen Gordon</signatureName>
        <signatureDate>2019-05-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
