<SUBMISSION>
<ACCESSION-NUMBER>0001235802-05-000076
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>2
<PERIOD>20050726
<FILING-DATE>20050727
<DATE-OF-FILING-DATE-CHANGE>20050727
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>MARTEN TRANSPORT LTD
<CIK>0000799167
<ASSIGNED-SIC>4213
<IRS-NUMBER>391140809
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>129 MARTEN ST
<CITY>MONDOVI
<STATE>WI
<ZIP>54755
<PHONE>7159264216
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>3400 PLAZA VII
<STREET2>45 SOUTH SEVENTH ST
<CITY>MINNEAPOLIS
<STATE>MN
<ZIP>55402
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>NASH TIMOTHY P
<CIK>0001253980
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-15010
<FILM-NUMBER>05976589
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>129 MARTEN STREET
<CITY>MONDOVI
<STATE>WI
<ZIP>54755
<PHONE>7159264216
</BUSINESS-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-07-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001253980</rptOwnerCik>
            <rptOwnerName>NASH TIMOTHY P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>129 MARTEN STREET</rptOwnerStreet1>
            <rptOwnerStreet2></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>Exec. VP of Sales &amp; Marketing</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-07-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.55</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-07-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>24.3901</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.55</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-07-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.55</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2010-01-24</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2625</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The number of option shares are exercisable as follows:  1,125 shares as of 1/24/01 and 1,125 shares on each of 1/24/02, 1/24/03, 1/24/04 and 1/24/05.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Timothy P. Nash, by James J. Hinnendael, as attorney-in-fact</signatureName>
        <signatureDate>2005-07-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>poa-nash.txt
<DESCRIPTION>POWER OF ATTORNEY
<TEXT>
POWER OF ATTORNEY

Know all by these presents, that the undersigned
hereby constitutes and appoints each of Darrell D. Rubel
and James J. Hinnendael, signing singly, the
undersigned's true and lawful attorney-in-fact to:
		(1) 	execute for and on behalf
of the undersigned, in the undersigned's capacity
as an officer and/or director of Marten Transport,
Ltd. (the "Company"), Forms 3, 4 and 5 in
accordance with Section 16(a) of the Securities Exchange
Act of 1934, as amended, and the rules
promulgated thereunder from time to time (collectively,
the "Act");
		(2) 	do and perform any and all acts
for and on behalf of the undersigned which
may be necessary or desirable to complete and execute
any such Form 3, 4 or 5, complete and
execute any amendment or amendments thereto, and
timely file such form with the United States
Securities and Exchange Commission and any stock
exchange or similar authority; and
		(3) 	take any other action of
any type whatsoever in connection with the
foregoing which, in the opinion of such
attorney-in-fact, may be of benefit to,
in the best interest
of, or legally required by, the undersigned,
it being understood that the documents
executed by such attorney-in-fact on behalf
of the undersigned pursuant to this Power of
Attorney shall be in
such form and shall contain such terms
and conditions as such attorney-in-fact may approve in
such attorney-in-fact's discretion.

The undersigned hereby grants to each such
attorney-in-fact full power and authority to
do and perform
any and every act and thing whatsoever requisite,
necessary, or proper to be done in the exercise
of any of
the rights and powers herein granted, as fully
to all intents and purposes as the undersigned
might or could do if personally present, with
full power of substitution or revocation,
hereby ratifying and confirming all that such
attorney-in-fact, or such attorney-in-fact's
substitute or substitutes, shall lawfully
do or cause to be done by virtue of this power
of attorney and the rights and powers herein
granted. The undersigned acknowledges that the
foregoing attorneys-in-fact, in serving in such
capacity at the request
of the undersigned, are not assuming, nor is the
Company assuming, any of the undersigned's
responsibilities to comply with the Act.

This Power of Attorney shall remain in full force
and effect until the undersigned is no longer
required to file Forms 3, 4 and 5 with respect
to the undersigned's holdings of and transactions
in securities issued by the Company, unless earlier
revoked by the undersigned in a signed writing
delivered to the foregoing
attorneys-in-fact.

	IN WITNESS WHEREOF, the undersigned has
caused this Power of Attorney to be executed as
of this 23rd day of January, 2003.

/s/ Timothy P. Nash
Signature
Timothy P. Nash
Print Name


</TEXT>
</DOCUMENT>
</SUBMISSION>
