Buster Crabbe

Flash Gordon

Carol Hughes

Dale Arden

Charles Middleton

Emperor Ming

Anne Gwynne

Sonja

Frank Shannon

Dr. Zarkov

John Hamilton

Professor Gordon

Herbert Rawlinson

Dr. Frohmann

Tom Chatterton

Professor Arden

Shirley Deane

Princess Aura

Lee Powell

Captain Roka

Roland Drew

Prince Barin

Don Rowan

Captain Torch

Victor Zimmerman

Lieutenant Thong

Edgar Edwards

Captain Turan

Michael Mark

Professor Karm

Earl Dwire

Janda

Harry C. Bradley

Keedish

Sigurd Nilssen

Count Korro

Mimi Taylor

Verna

Byron Foulger

Professor Drok

William Royle

Captain Sudan

Donald Curtis

Ronal (uncredited)

Luli Deste

Queen Fria (uncredited)

Ben Taggart

General Lupi (uncredited)

Allan Cavan

Man with Thinking Brain (uncredited)

Jack Roper

Man of Low Intellect (uncredited)

Reed Howes

Barin's Ship #5 Commander (uncredited)

Charles Sherlock

Guard Kroad (uncredited)

Mala

Prince of the Rock People (uncredited)

Chief Yowlachie

King of the Rock People (uncredited)

Jack Gardner

Professor Gordon's Radio Operator (uncredited)

Joey Ray

Professor Gordon's Assistant (uncredited)

Roy Barcroft

Ming's Soldier / Arborian Sentry (uncredited)

Lane Chandler

Ming's Soldier (uncredited)

Gene Rizzi

Ming's Soldier (uncredited)

Wheaton Chambers

Scientist (uncredited)

John Elliott

Scientist (uncredited)

Jack George

Scientist (uncredited)

Jean Brooks

Olga (uncredited)

Carmen D'Antonio

Ming's Dancing Girl (uncredited)

Vivian Mason

Ming's Gong Girl (uncredited)

Ernie Adams

(uncredited)

Clarice Sherry

(uncredited)

Tom Steele

Ming's Pilot (uncredited)

Eddie Parker

Arborian Prison Guard (uncredited)

Bill Hunter

Guard (uncredited)

Robert Blair

(uncredited)

Harold Daniels

(uncredited)

Pat Gleason

(uncredited)

Ernie Payson

(uncredited)

Paul Reed

(uncredited)

Charles Waldron Jr.

(uncredited)

Saul A. Goodkind

Various Characters (voice) (uncredited)