The auction, on September 26, will coincide with National Wild Horse Adoption Day, during which the bureau and wild horse advocacy groups hope 1000 mustangs will be given new homes around the country.
The Pryor Mountain herd has been made famous by the documentaries of Ginger Kathrens, who had campaigned hard to stop the federal muster of the 188 horses that lived in the mountains.
However, the muster went ahead, largely meeting the bureau's plan to reduce the herd size to 120.
The auction of the Pryor Mountain horses will be held at the Britton Springs corrals north of Lovell, Wyoming. The facility will also be open all day on September 25 for horse viewing and registration.
The adoption will include 24 male and 33 female horses, including three mare-foal pairs. The horses range in age from 0-22 years.
The gates will open both days at 8am, with bidding to begin on September 26 at noon.
The minimum bid for each animal is $US125. The starting bid for pairs is $US250. Successful bidders will be able to load their horse(s) as soon as the adoption concludes.
Ken McNabb, a professional horse trainer, instructor and clinician from Clark, Wyoming, will be holding clinics on both days, and also hosts a show on RFD television.
More information on National Wild Horse Adoption Day can be found here