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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2017-09-19</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001711279</issuerCik>
        <issuerName>Krystal Biotech, Inc.</issuerName>
        <issuerTradingSymbol>KRYS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001717325</rptOwnerCik>
            <rptOwnerName>Ganorkar Kirti</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SUN HOUSE, 201-B/1, WESTERN EXPRESS HWY</rptOwnerStreet1>
            <rptOwnerStreet2>GOREGAON EAST</rptOwnerStreet2>
            <rptOwnerCity>MUMBAI, INDIA</rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode>400063</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <footnotes></footnotes>

    <remarks>Exhibit 24.1 Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>/s/ Katherine A. Shaia, as attorney-in-fact for Kirti Ganorkar</signatureName>
        <signatureDate>2017-09-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
