José Ferrer as Captain Nemo

Burgess Meredith as Prof. Waldo Cunningham

Mel Ferrer as Dr. Robert Cook

Horst Buchholz as King Tibor

Tom Hallick as Comdr. Tom Franklin

Burr DeBenning as Lt. Jim Porter

Lynda Day George as Kate

Warren Stevens as Miller

Med Flory as Tor

Anthony McHugh as Radio Operator

Randolph Roberts as Helmsman

Richard Angarola as Trog

Anthony Geary as Bork

Stephen Powers as Lloyd

Yale Summers as Sirak