Full Cast — Lost in Space (1965–1968)

Guy Williams

Dr. John Robinson

June Lockhart

Dr. Maureen Robinson

Mark Goddard

Major Don West

Marta Kristen

Judy Robinson

Angela Cartwright

Penny Robinson

Bill Mumy

Will Robinson

Jonathan Harris

Dr. Zachary Smith

Dick Tufeld

Robot B-9

Bob May

Robot B-9

Dawson Palmer

Monster / Android Raddion / Cosmic Monster / Keel / IDAK Omega 17 / Angus / Moss monster / Bog Monster / Creature

Fritz Feld

Mr. Zumdish

Sheila Allen

Ruth Templeton / Aunt Gamma / Brynhilda

Ron Gans

Frog Alien (voice) / Alien Leader / Creature (voice)

Dee Hartford

Nancy Pi Squared / Verda

Leonard Stone

Farnum

Albert Salmi

Captain Alonzo P. Tucker

Michael Rennie

The Keeper

Vitina Marcus

Athena / Lorelei

Michael Fox

Alien on Computer Screen (voice) / Cybernetic Leader / Supreme Brain (voice)

Don Matheson

IDAK Alpha 12 / Rethso

Joe E. Tata

Purple Robot (voice) / Zalto's Dummy (voice)

Don Forbes

TV Commentator

Theodore Lehmann

Disk (voice) / Alien

Gregory Morton

Canto of Quasti (voice) / Judge Iko (voice)

Allan Melvin

Little Joe / Gambling Machine (voice) / Enforcer Claudio

Tiger Joe Marsh

Security Guard / Elevator Operator

Hoke Howell

Sgt. Rogers / Security Guard

Sue England

Female Robot (voice) / Space Control Officer O-3 (voice)

William Bramley

Robotoid (voice) (uncredited) / Mr. Nobody

Keith Taylor

Theodore the bully / Edgar

Robert Foulk

Cragmire / Kraspo

Marcel Hillaire

Junkman / Phanzig

Fred Krone

Monster / Chronos' Alien Assistant