Buster Crabbe
Flash Gordon (archive footage)
Jean Rogers
Dale Arden (archive footage)
Frank Shannon
Dr. Hans Zarkov (archive footage)
Charles Middleton
Ming the Merciless (archive footage)
Priscilla Lawson
Princess Aura (archive footage)
Richard Alexander
Prince Barin (archive footage)
Jack 'Tiny' Lipson
King Vultan (archive footage)
James Pierce
Prince Thun (archive footage)
Earl Askam
Officer Torch (archive footage)
Richard Tucker
Prof. Gordon (archive footage)
George Cleveland
Prof. Henson (archive footage)
Lon Poff
The High Priest (archive footage)
Charles McMurphy
Atom Furnace supervisor (archive footage)
Theodore Lorch
Priest #2 (archive footage)
Duke York
(scenes deleted) (archive footage) (as Duke York Jr.)
Lynton Brent
Transcontinental airplane pilot (archive footage) (uncredited)
Al Ferguson
Telescreen monitor (archive footage) (uncredited)
Fred Kohler Jr.
Robot / Ming soldier (archive footage) (uncredited)
Bull Montana
Monkey-Man (archive footage) (uncredited)
Constantine Romanoff
Monkey-Man (archive footage) (uncredited)
Glenn Strange
Robot / Ming soldier / Gocko (archive footage) (uncredited)
Harry Wilson
Captured soldier (archive footage) (uncredited)