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)

Devi Morgan as Background (uncredited)