William Shatner 
 as Admiral James T. Kirk

Leonard Nimoy 
 as Captain Spock

Ricardo Montalban 
 as Khan Noonien Singh

DeForest Kelley 
 as Dr. Leonard 'Bones' McCoy

James Doohan 
 as Cmdr. Montgomery 'Scotty' Scott

Walter Koenig 
 as Cmdr. Pavel Chekov

George Takei 
 as Cmdr. Hikaru Sulu

Nichelle Nichols 
 as Cmdr. Uhura

Bibi Besch 
 as Dr. Carol Marcus

Merritt Butrick 
 as Dr. David Marcus

Paul Winfield 
 as Captain Clark Terrell

Kirstie Alley 
 as Lt. Saavik

Judson Scott 
 as Joachim

Ike Eisenmann 
 as Preston

John Vargas 
 as Jedda

John Winston 
 as Kyle

Paul Kent 
 as Beach

Nicholas Guest 
 as Cadet

Russell Takaki 
 as Madison

Kevin Rodney Sullivan 
 as March

Joel Marston 
 as Crew Chief

Laura Banks 
 as Khan's Navigator

Steve Bond 
 as Khan's Crewman #1

Brett Baxter Clark 
 as Khan's Crewman #2

Gilbert B. Combs 
 as Enterprise Engineer

James Horner 
 as Enterprise Crewman

George Sasaki 
 as Crewmember at Spock's Funeral (uncredited)

Teresa E. Victor 
 as Bridge Voice

Dianne Harper 
 as Radio Voice

David Ruprecht 
 as Radio Voice (credited as David Ruprecht)

Marcy Vosburgh 
 as Computer Voice

Bill Baker 
 as Enterprise Trainee (uncredited)

Steve Blalock 
 as Trainee Crewmember (uncredited)

Fletcher Bryant 
 as Khan's Crewman (uncredited)

Bobby Burns 
 as Crew Member at Spock's Funeral (uncredited)

Diane Carter 
 as Regula I Scientist (uncredited)

Ann Chatterton 
 as Khan Crew Member (uncredited)

Tim Culbertson 
 as Khan's Henchman (uncredited)

Eddy Donno 
 as Corpse of Regula I Cook (uncredited)

John Gibson 
 as Khan's Crewman #4 (uncredited)

Richard Forinash 
 as Enterprise Torpedo Officer (uncredited)

Anthony Gordon 
 as Regula I Steward (uncredited)

Ree Kai 
 as Enterprise Trainee (uncredited)

Hubie Kerns Jr. 
 as Enterprise Engineer Trainee (uncredited)

Dennis Landry 
 as Khan's Crewman #5 (uncredited)

Cristian Letelier 
 as Khan's Crewman #6 (uncredited)

Jeff McBride 
 as Khan's Crewman (uncredited)

Jeff McBride 
 as Human Augment (uncredited)

Roger Menache 
 as Khan's Crewman #7 (uncredited)

Tom Morga 
 as Starfleet Astronaut (uncredited)

Jim Painter 
 as Crewmember at Spock's Funeral (uncredited)

Nanci Rogers 
 as Khan's Crew Member (uncredited)

Tony Roque 
 as Enterprise Engineer (uncredited)

Kimberly L. Ryusaki 
 as Enterprise Trainee (uncredited)

John Bear Staible 
 as Enterprise Crewmember (uncredited)

Deney Terrio 
 as Khan's Crewman #11 (uncredited)

Philip Weyland 
 as Starfleet Crewman (uncredited)

Daniel Wong 
 as Enterprise Engineer Cadet (uncredited)