William Shatner

Character: Admiral James T. Kirk

DeForest Kelley

Character: Dr. Leonard 'Bones' McCoy

James Doohan

Character: Captain Montgomery 'Scotty' Scott

George Takei

Character: Cmdr. Hikaru Sulu

Walter Koenig

Character: Cmdr. Pavel Chekov

Nichelle Nichols

Character: Cmdr. Uhura

Christopher Lloyd

Character: Cmdr. Kruge

Robin Curtis

Character: Lt. Saavik

Mark Lenard

Character: Ambassador Sarek

Merritt Butrick

Character: Dr. David Marcus

Judith Anderson

Character: Vulcan High Priestess

James B. Sikking

Character: Captain Styles

Phillip R. Allen

Character: Capt. Esteban

Robert Hooks

Character: Admiral Morrow

John Larroquette

Character: Maltz

Carl Steven

Character: Spock...Age 9

Vadia Potenza

Character: Spock...Age 13

Stephen Manley

Character: Spock...Age 17

Joe W. Davis

Character: Spock at age 25

Leonard Nimoy

Character: Captain Spock / Elevator Voice

Miguel Ferrer

Character: First Officer

Branscombe Richmond

Character: Klingon Gunner #2

Frank Welker

Character: Spock's Screams

Scott McGinnis

Character: Starfleet Cadet "Mr. Adventure"

Phil Morris

Character: Trainee Foster

Jeanne Mori

Character: Helm Officer

Grace Lee Whitney

Character: Commander Janice Rand (Woman in Cafeteria)

Nanci Rogers

Character: Bar Waitress (uncredited)

Paul Sorensen

Character: Captain

Danny Rogers

Character: Merchantman First Officer (uncredited)