<SEC-DOCUMENT>0001881752-25-000003.txt : 20250508
<SEC-HEADER>0001881752-25-000003.hdr.sgml : 20250508
<ACCEPTANCE-DATETIME>20250508170134
ACCESSION NUMBER:		0001881752-25-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250506
FILED AS OF DATE:		20250508
DATE AS OF CHANGE:		20250508

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Petit Douglas Paul
		CENTRAL INDEX KEY:			0001881752
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-15010
		FILM NUMBER:		25927215

	MAIL ADDRESS:	
		STREET 1:		C/O MARTEN TRANSPORT, LTD.
		STREET 2:		129 MARTEN STREET
		CITY:			MONDOVI
		STATE:			WI
		ZIP:			54755

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARTEN TRANSPORT LTD
		CENTRAL INDEX KEY:			0000799167
		STANDARD INDUSTRIAL CLASSIFICATION:	TRUCKING (NO LOCAL) [4213]
		ORGANIZATION NAME:           	01 Energy & Transportation
		EIN:				391140809
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		129 MARTEN STREET
		CITY:			MONDOVI
		STATE:			WI
		ZIP:			54755
		BUSINESS PHONE:		715-926-4216

	MAIL ADDRESS:	
		STREET 1:		129 MARTEN STREET
		CITY:			MONDOVI
		STATE:			WI
		ZIP:			54755
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-05-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000799167</issuerCik>
        <issuerName>MARTEN TRANSPORT LTD</issuerName>
        <issuerTradingSymbol>MRTN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001881752</rptOwnerCik>
            <rptOwnerName>Petit Douglas Paul</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MARTEN TRANSPORT, LTD.</rptOwnerStreet1>
            <rptOwnerStreet2>129 MARTEN STREET</rptOwnerStreet2>
            <rptOwnerCity>MONDOVI</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>54755</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-05-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6625</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>36461</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares granted under a Performance Unit Award Agreement will vest in equal increments over five years beginning on December 31, 2025.</footnote>
        <footnote id="F2">Includes: (i) 6,625 shares granted under a Performance Unit Award Agreement that vest on 12/31/2025 through 12/31/2029; (ii) 3,992 shares granted under a Performance Unit Award Agreement that vest on 12/31/2025 through 12/31/2028; (iii) 2,578 shares granted under a Performance Unit Award Agreement that vest on 12/31/2025 through 12/31/2027; (iv) 2,050 shares granted under a Performance Unit Award Agreement that vest on 12/31/2025 through 12/31/2026; and (v) 200 shares granted under a Performance Unit Award Agreement that vest on 12/31/2025.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ James J. Hinnendael, attorney-in-fact</signatureName>
        <signatureDate>2025-05-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
