Helen Hayes as Catherine Barkley

Gary Cooper as Lt. Frederic Henry

Adolphe Menjou as Major Rinaldi

Mary Philips as Helen Ferguson

Jack La Rue as Priest

Blanche Friderici as Head Nurse

Mary Forbes as Miss Van Campen

Gilbert Emery as British Major

Henry Armetta as Bonello the Ambulance Driver (uncredited)

Herman Bing as Swiss Postal Clerk (uncredited)

Agostino Borgato as Hospital Porter Giulio (uncredited)

Marcelle Corday as Swiss Nurse (uncredited)

Gino Corrado as Italian Soldier (uncredited)

William Irving as Frustrated Opera Singing Friend (uncredited)

Doris Lloyd as Nurse (uncredited)