Roy Scheider

Dr. Heywood Floyd

John Lithgow

Dr. Walter Curnow

Helen Mirren

Tanya Kirbuk

Bob Balaban

Dr. R. Chandra

Keir Dullea

Dr. David Bowman

Douglas Rain

HAL 9000 (voice)

Madolyn Smith Osborne

Caroline Floyd

Savely Kramarov

Dr. Vladimir Rudenko

Taliesin Jaffe

Christopher Floyd

James McEachin

Victor Milson

Mary Jo Deschanel

Betty Fernandez

Ilya Baskin

Maxim Brailovsky

Dana Elcar

Dimitri Moisevitch

Oleg Rudnik

Dr. Vasili Orlov

Natasha Shneider

Irina Yakunina

Vladimir Skomarovsky

Yuri Svetlanov

Victor Steinbach

Nikolaj Ternovsky

Candice Bergen

SAL 9000 (voice)

Gene McGarr

Commercial Announcer

Herta Ware

Jessie Bowman

Jan Tříska

Alexander Kovalev

Larry Carroll

Anchorman on TV

Cheryl Carter

Nurse

Ron Recasner

Hospital Neurosurgeon

Robert Lesser

Dr. Hirsch

Delana Michaels

Commercial Announcer

Arthur C. Clarke

Man on Park Bench (uncredited)