EXHIBIT 5

                           [FAEGRE & BENSON LLP LOGO]

                      UNITED STATES ENGLAND GERMANY CHINA

                                  June 22, 2005

Board of Directors
Smithway Motor Xpress Corp.
2031 Quail Avenue
Fort Dodge, Iowa 50501

Ladies and Gentlemen:

      In connection with the Registration Statement on Form S-8 under the
Securities Act of 1933, as amended (the "Registration Statement"), relating to
the registration of (a) the Smithway Motor Xpress Corp. 2005 Omnibus Stock Plan
(the "Plan"), authorizing the issuance of up to 500,000 shares of Class A Common
Stock, par value $0.01 per share (the "Shares"), of Smithway Motor Xpress Corp.,
a Nevada corporation (the "Company"), and (b) 12,000 Shares to be issued by the
Company pursuant to the terms of the non-employee director option agreements,
dated July 27, 2000, between the Company and each of Terry G. Christenberry,
Herbert D. Ihle and Robert E. Rich (collectively, the "Option Agreements"), we
have examined such corporate records and other documents, including the
Registration Statement, the Plan and the Option Agreements, and have reviewed
such matters of law as we have deemed relevant hereto, and, based upon such
examination and review, it is our opinion that all necessary corporate action on
the part of the Company has been taken to authorize the issuance and sale of the
Shares pursuant to the Plan and the Option Agreements, and that, when issued and
sold as contemplated in the Registration Statement, the Shares will be legally
and validly issued, fully paid and nonassessable under the current laws of the
State of Nevada.

      We are admitted to practice in the State of Minnesota; however, we are not
admitted to practice in the State of Nevada. For the limited purposes of our
opinion set forth above, we are generally familiar with the law of Business
Associations, Securities and Commodities of Nevada, contained in Title 7 of the
Nevada Revised Statutes ("NRS Title 7") as presently in effect and have made
such inquiries as we consider necessary to render this opinion with respect to a
Nevada corporation. Subject to the foregoing, this opinion letter is limited to
the laws of NRS Title 7 and federal law as such laws presently exist and to the
facts as they presently exist. We express no opinion with respect to the effect
or applicability of the laws of any other jurisdiction.

      We consent to the filing of this opinion as an exhibit to the Registration
Statement.

                                                         Very truly yours,

                                                         FAEGRE & BENSON LLP

                                                         By: /s/ W. Morgan Burns
                                                            --------------------
                                                             W. Morgan Burns