• 
  Gregg Palmer

  Jed Grant
• 
  Leigh Snowden

  Marcia Barton
• 
  Rex Reason

  Dr. Thomas Morgan
• 
  Don Megowan

  The Gill Man (on land)
• 
  Frank Chase

  Steward
• 
  Paul Fierro

  Morteno
• 
  Larry Hudson

  State Trooper
• 
  Maurice Manson

  Dr. Borg

• 
  David McMahon

  Captain Stanley
• 
  Lillian Molieri

  Mrs. Morteno
• 
  Jeff Morrow

  Dr. William Barton
• 
  Gregg Palmer

  Jed Grant
• 
  James Rawley

  Dr. Johnson

• 
  Alexander Golitzen

  art director
• 
  Robert Emmet Smith

  art director

• 
  Clifford Stine

  camera and electrical departme
• 
  Maury Gertsman

  imagine
• 
  Henry Mancini

  departament sunet
• 
  Heinz Roemheld

  departament sunet
• 
  Irving Gertz

  departament sunet
• 
  Edward Curtiss

  montaj
• 
  George Hamilton

  make-up department
• 
  Herman Stein

  music department
• 
  Hans J. Salter

  music department
• 
  Joseph Gershenson

  music department
• 
  William Alland

  producător
• 
  John P. Austin

  set decorator
• 
  Russell A. Gausman

  set decorator
• 
  Leslie I. Carey

  sound department
• 
  Arthur A. Ross

  scriitor