Faye Dunaway
as Diana Christensen

William Holden
as Max Schumacher

Peter Finch
as Howard Beale

Robert Duvall
as Frank Hackett

Ned Beatty
as Arthur Jensen

Beatrice Straight
as Louise Schumacher

Wesley Addy
as Nelson Chaney

Arthur Burghardt
as Great Ahmed Kahn

Bill Burrows
as TV Director

John Carpenter
as George Bosch

Jordan Charney
as Harry Hunter

Kathy Cronkite
as Mary Ann Gifford

Ed Crowley
as Joe Donnelly

Jerome Dempsey
as Walter C. Amundsen

Conchata Ferrell
as Barbara Schlesinger

Gene Gross
as Milton K. Steinman

Stanley Grover
as Jack Snowden

Cindy Grover
as Caroline Schumacher

Darryl Hickman
as Bill Herron

Mitchell Jason
as Arthur Zangwill

Paul Jenkins
as TV Stage Manager

Ken Kercheval
as Merrill Grant

Kenneth Kimmins
as Associate Producer

Lynn Klugman
as TV Production Assistant

Carolyn Krigbaum
as Max's Secretary

Zane Lasky
as Audio Man

Michael Lipton
as Tommy Pellegrino

Michael Lombard
as Willie Stein

Pirie MacDonald
as Herb Thackeray

Russ Petranto
as TV Associate Director

Bernard Pollock
as Lou

Roy Poole
as Sam Haywood

William Prince
as Edward George Ruddy

Sasha von Scherler
as Helen Miggs

Lane Smith
as Robert McDonough

Ted Sorel
as Giannini

Fred Stuthman
as Mosaic Figure

Cameron Thomas
as TV Technical Director

Marlene Warfield
as Laureen Hobbs

Lydia Wilen
as Hunter's Secretary

Lee Richardson
as Narrator (voice)

Lance Henriksen
as Network Lawyer at Khan's Place (uncredited)