Ellen Burstyn as Chris MacNeil

Linda Blair as Regan MacNeil

Jason Miller as Father Damien Karras

Max von Sydow as Father Lankester Merrin

Lee J. Cobb as Lt. Bill Kinderman

William O'Malley as Father Joseph Kevin Dyer

Kitty Winn as Sharon Spencer

Jack MacGowran as Burke Dennings

Barton Heyman as Dr. Klein

Peter Masterson as Dr. Barringer

Rudolf Schündler as Karl

Gina Petrushka as Willi

Robert Symonds as Dr. Taney

Arthur Storch as Psychiatrist

Thomas Bermingham as Tom

Vasiliki Maliaros as Mary Karras

Titos Vandis as Uncle John

John Mahon as Language Lab Director

Wallace Rooney as Bishop Michael

Ron Faber as Chuck / Demon (voice)

Donna Mitchell as Mary Jo Perrin

Roy Cooper as Jesuit Dean

Robert Gerringer as Senator at Party

Mercedes McCambridge as Demon (voice)

Paul Bateson as Radiologist's Assistant (uncredited)

Elinore Blair as Nurse (uncredited)

William Peter Blatty as The Producer (uncredited)

Mary Boylan as First Mental Patient (uncredited)

Dick Callinan as Astronaut (uncredited)

Mason Curry as Doctor (voice) (uncredited)

Toni Darnay as Violent psychotic patient (uncredited)

Eileen Dietz as Demon / Regan Double (uncredited)

Joanne Dusseau as Senator's Wife (uncredited)

Bernard Eismann as Minor Role (uncredited)

Beatrice Hunter as Minor Role (uncredited)

Yvonne Jones as Bellevue Nurse (uncredited)

Don LaBonte as Minor Role (uncredited)

Barton Lane as Angiography Doctor (uncredited)

Ann Miles as Spiderwalk (uncredited)

John Nicola as Priest (uncredited)

Vincent Russell as Subway Vagrant (uncredited)

Gerard F. Yates as Priest Singing Around Piano at Party (uncredited)

Rita Sakellariou as (her voice on the radio)