Jerry Lewis as John Paul Steckler I / John Paul Steckler IV / John Paul Steckler VII

Dina Merrill as Ens. Rita J. Benson

Diana Spencer as Prudence Trabert Steckler

Mickey Shaughnessy as Stan Wychinski

Robert Middleton as Vice Adm. Philo Tecumseh Bludde

Gale Gordon as Congressman Mandeville

Mabel Albertson as Mrs. Trabert

Claude Akins as Lt. Cmdr. Farber

Hugh Sanders as Adm. Rogers

Richard Shannon as Cmdr. Cross

Chuck Wassil as Cmdr. Craig

Burt Metcalfe as Lt. Bond

Pamela Duncan as Lt. Ward

Karl Lukas as Dugan

George Sasaki as Asian Crewman (uncredited)

Martin Smith as Officer (uncredited)