Jack Nicholson as Randle Patrick McMurphy

Brad Dourif as Billy Bibbit

Louise Fletcher as Nurse Mildred Ratched

Danny DeVito as Martini

William Redfield as Dale Harding

Scatman Crothers as Orderly Turkle

Christopher Lloyd as Max Taber

Will Sampson as Chief Bromden

Dean R. Brooks as Dr. John Spivey

Michael Berryman as Ellis

Sydney Lassick as Charlie Cheswick

William Duell as Jim Sefelt

Vincent Schiavelli as Bruce Fredrickson

Peter Brocco as Col. Matterson

Alonzo Brown as Miller

Mwako Cumbuka as Warren

Josip Elic as Bancini

Ken Kenny as Beans Garfield

Nathan George as Washington

Ted Markland as Hap Arlich

Louisa Moritz as Rose

Mews Small as Candy

Delos V. Smith Jr. as Scanlon

Lan Fendors as Nurse Itsu

Mimi Sarkisian as Nurse Pilbow

Mel Lambert as Harbor Master

Kay Lee as Night Supervisor

Dwight Marfield as Ellsworth

Tin Welch as Ruckley

Philip Roth as Woolsey

Aurore Clément as Lady on Pier (uncredited)

Anjelica Huston as Woman in Crowd on Pier (uncredited)

Audrey Landers as Actress on TV Screen (uncredited)

Saul Zaentz as Captain on Shore (uncredited)