Richard Carlson
Dr. David Reed
Richard Carlson
Dr. David Reed
Julie Adams
Kay Lawrence
Richard Denning
Dr. Mark Williams
Antonio Moreno
Dr. Carl Maia
Nestor Paiva
Captain Lucas
Whit Bissell
Dr. Edwin Thompson
Bernie Gozier
Zee
Henry A. Escalante
Chico
Ricou Browning
The Gill Man In Water (uncredited)
Ben Chapman
The Gill Man On Land (uncredited)
Art Gilmore
Narrator (voice) (uncredited)
Perry Lopez
Tomas (uncredited)
Sydney Mason
Dr. Matos (uncredited)
Rodd Redwing
Luis (uncredited)
James Miller
Old Man (uncredited)
William E. Snyder
Director of Photography
Jack Arnold
Director
William Alland
Producer
Hans J. Salter
Original Music Composer
Henry Mancini
Original Music Composer
Harry Essex
Screenplay
Herman Stein
Original Music Composer
Arthur A. Ross
Screenplay
Ted J. Kent
Editor
Jack N. Young
Stunts
James R. Wolfe
Driver
Gene Poole
Stunts
Ginger Stanley
Stunts
William Alland
Idea
Russ Haverick
Assistant Director
Foster Thompson
Unit Manager
Al Wyatt Sr.
Stunts
Everett Brown
Grip
Ethmer Roten
Musician
Ted White
Stunts
Jack Kevan
Makeup Artist
Chris Mueller
Makeup Artist
Ray Craddock
Sound Editor
Robert Hickman
Makeup Artist
Albert E. Kennedy
Sound Editor
Hilyard M. Brown
Art Direction
Joan St. Oegger
Hairstylist
Bud Westmore
Makeup Artist
Maurice Zimm
Story
Ray Jeffers
Set Decoration
Russell A. Gausman
Set Decoration
Bernard Herzbrun
Art Direction
Joe Lapis
Sound
Leslie I. Carey
Sound
Scotty Welbourne
Still Photographer
James Curtis Havens
Underwater Camera
Milicent Patrick
Makeup Designer
E. Thomas Case
Makeup Artist
Milicent Patrick
Creature Design
Fred Frank
Assistant Director
Polly Burson
Stunt Double
Joseph Gershenson
Music Director
Evan Baldwin
Special Effects
Rosemary Odell
Wardrobe Master
Robert Emmett Dolan
Additional Music
Milton Rosen
Additional Music