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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2020-03-12</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001583648</issuerCik>
        <issuerName>PIERIS PHARMACEUTICALS, INC.</issuerName>
        <issuerTradingSymbol>PIRS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001591986</rptOwnerCik>
            <rptOwnerName>Aquilo Capital Management, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE LETTERMAN DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE D4900, BUILDING D</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94129</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $0.001 par value</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5575530</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Warrants</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>7.1</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2019-11-04</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-11-04</value>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, $0.001 par value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1126761</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting persons are Aquilo Capital Management, LLC (&quot;Aquilo&quot;) and Marc R. Schneidman. Aquilo is the general partner and investment adviser of investment funds that hold these securities directly for the benefit of their investors. Aquilo may be deemed to beneficially own such securities indirectly as the investment adviser and general partner of those funds, and Mr. Schneidman may be deemed to beneficially own them indirectly as the control person of Aquilo. Each of Aquilo and Mr. Schneidman disclaims beneficial ownership of such securities except to the extent of his or its pecuniary interest therein.</footnote>
        <footnote id="F2">The warrants are exercisable at any time, at the holder's election, except that the warrants may not be exercised if, after such exercise, the Reporting Person would beneficially own, as determined in accordance with Section13(d) of the Exchange Act, more than 9.99% of the number of shares of Common Stock then issued and outstanding.</footnote>
        <footnote id="F3">The warrants may expire earlier if the Issuer meets certain performance conditions.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Aquilo Capital Management, LLC By: Managing Member /s/ Marc Schneidman</signatureName>
        <signatureDate>2020-03-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
