Ellen Burstyn
Chris MacNeil

Linda Blair
Regan MacNeil

Jason Miller
Father Damien Karras

Max von Sydow
Father Lankester Merrin

Lee J. Cobb
Lt. Bill Kinderman

William O'Malley
Father Joseph Kevin Dyer

Kitty Winn
Sharon Spencer

Jack MacGowran
Burke Dennings

Barton Heyman
Dr. Klein

Peter Masterson
Dr. Barringer

Rudolf Schündler
Karl

Gina Petrushka
Willi

Robert Symonds
Dr. Taney

Arthur Storch
Psychiatrist

Thomas Bermingham
Tom

Vasiliki Maliaros
Mary Karras

Titos Vandis
Uncle John

John Mahon
Language Lab Director

Wallace Rooney
Bishop Michael

Ron Faber
Chuck / Demon (voice)

Donna Mitchell
Mary Jo Perrin

Roy Cooper
Jesuit Dean

Robert Gerringer
Senator at Party

Mercedes McCambridge
Demon (voice)

William Peter Blatty
The Producer (uncredited)

Mary Boylan
First Mental Patient (uncredited)

Eileen Dietz
Demon / Regan Double (uncredited)

Rita Sakellariou
(her voice on the radio)