UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

March 13, 2006

MARTEN TRANSPORT, LTD.

(Exact name of registrant as specified in its charter)

Delaware	0-15010	39-1140809
(State or other jurisdiction of incorporation)	(Commission File Number)	(I.R.S. Employer Identification Number)
129 Marten Street Mondovi, Wisconsin		54755
(Address of principal executive offices)		(Zip Code)

(715) 926-4216

(Registrant’s telephone number, including area code)

Not applicable.

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 1.01. Entry into a Material Definitive Agreement.

On March 13, 2006, Marten Transport, Ltd. entered into the tenth amendment to its unsecured committed credit facility with U.S. Bank National Association dated October 30, 1998. This amendment increased the total facility from $45.0 million to $55.0 million through August 2006, at which time the amount of the credit facility will return to $45.0 million. The foregoing summary of the amendment is not complete and is qualified in its entirety by reference to the complete text of such document, which is filed as Exhibit 10.1 to this current report on Form 8-K and is incorporated herein by reference.

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Item 9.01. Financial Statements and Exhibits.

(a)Financial Statements of Businesses Acquired.

Not Applicable.

(b)Pro Forma Financial Information.

Not Applicable.

(c)Exhibits.

Exhibit No.	Description
10.1	Tenth Amendment to Credit Agreement, dated March 13, 2006, between the Company and U.S. Bank National Association.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

	MARTEN TRANSPORT, LTD.
Dated:  March 13, 2006	By	/s/ James J. Hinnendael
		James J. Hinnendael
		Its: Chief Financial Officer

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MARTEN TRANSPORT, LTD.

FORM 8-K

INDEX TO EXHIBITS

Exhibit No.	Description
10.1	Tenth Amendment to Credit Agreement, dated March 13, 2006, between the Company and U.S. Bank National Association (included herewith).

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