*Gil Gerard as Capt. William "Buck" Rogers
- Erin Gray as Col. Wilma Deering
- Tim O'Connor as Dr. Elias Huer
- Gary Coleman as Hieronymous Fox
- Ray Walston as Roderick Zale
- Melody Rogers as Lt. Dia Cyrton
- Albert Popwell as Koren
- Earl Boen as Selmar
- Felix Silla as Twiki
- Mel Blanc as Voice of Twiki
- Lester Fletcher as M.D. Toman
- Tobar Mayo as Guard
- Tony Epper as Drunk
- William Conrad as Voice of Narrator (uncredited)
- Eric Server as Voice of Dr. Theopolis (uncredited)