John Wayne

Colonel Cord McNally

Jorge Rivero

Captain Pierre Cordona (Frenchy)

Jennifer O'Neill

Shasta Delaney

Jack Elam

Phillips

Christopher Mitchum

Seargent Tuscarora Phillips

Victor French

Ketcham

Susana Dosamantes

Maria Carmen

Sherry Lansing

Amelita

David Huddleston

Dr. Ivor Jones

Jim Davis

Rio Lobo Deputy

Robert Donner

Deputy Whitey Carter

George Plimpton

Fourth Gunman

Edward Faulkner

Lt. Harris

Peter Jason

Lt. Ned Forsythe

Chuck Courtney

Chuck

Robert Rothwell

Third Gunman

Bill Williams

Blackthorne Sheriff Pat Cronin

Mike Henry

Rio Lobo Sheriff 'Blue Tom' Hendricks

Hank Worden

Hank, the hotel desk clerk

Bob Steele

Rio Lobo Deputy (uncredited)

Chuck Roberson

Corporal in Baggage Car

Chuck Hayward

(uncredited)

Don 'Red' Barry

Feeny - Bartender (uncredited)

Sondra Currie

Blackthorne Prostitute (uncredited)

Conrad Hool

Bart (uncredited)

Lance Hool

Picket (uncredited)

John Hudkins

Rio Lobo Deputy (uncredited)

Richard LaMarr

Man in Army Post Saloon (uncredited)

John McKee

Rio Lobo Deputy (uncredited)

Boyd 'Red' Morgan

Train Engineer (uncredited)

William H. O'Brien

Man in Army Post Saloon (uncredited)

Gregg Palmer

Pete - Henchman (uncredited)

Chuck Roberson

Corporal in Baggage Car (uncredited)

Cap Somers

Card Player (uncredited)

Hank Worden

Hank - Hotel Clerk (uncredited)