EXHIBIT 24

                           SMITHWAY MOTOR XPRESS CORP.

                               Powers of Attorney

      The undersigned directors of Smithway Motor Xpress Corp., a Nevada
corporation, do hereby make, constitute and appoint G. Larry Owens and Douglas
C. Sandvig, and either of them, the undersigned's true and lawful
attorneys-in-fact, with power of substitution, for the undersigned and in the
undersigned's name, place and stead, to sign and file with the Securities and
Exchange Commission under the Securities Act of 1934, as amended, the Company's
Annual Report on Form 10-K for the year ended December 31, 2005, any and all
amendments and exhibits to such Annual Report on Form 10-K and any and all
applications, instruments, and other documents to be filed with the Securities
and Exchange Commission pertaining to such Annual Report on Form 10-K or any
amendments thereto, granting unto said attorneys-in-fact, and either of them,
full power and authority to do and perform any and all acts necessary or
incidental to the performance and execution of the powers herein expressly
granted.

      IN WITNESS WHEREOF, each of the undersigned have hereunto set their hands
as of March 27, 2006.

/s/ Terry G. Christenberry
- ---------------------------------------
Terry G. Christenberry

/s/ Labh S. Hira
- ---------------------------------------
Labh S. Hira

/s/ Herbert D. Ihle
- ---------------------------------------
Herbert D. Ihle

/s/ Marlys L. Smith
- ---------------------------------------
Marlys L. Smith