Cedric Hardwicke as Dr. Ludwig Frankenstein / Dr. Henry Frankenstein (ghostly image)

Ralph Bellamy as Erik Ernst

Lionel Atwill as Dr. Bohmer

Bela Lugosi as Ygor

Evelyn Ankers as Elsa Frankenstein

Lon Chaney Jr. as The Frankenstein Monster

Janet Ann Gallow as Cloestine Hussman

Barton Yarborough as Dr. Kettering

Doris Lloyd as Martha the Housekeeper

Leyland Hodgson as Chief Constable

Olaf Hytten as Adolph Hussman

Holmes Herbert as Magistrate

Richard Alexander as Villager at Council Meeting (uncredited)

Lionel Belmore as Councilman (uncredited)

Chet Brandenburg as Villager (uncredited)

Colin Clive as Dr. Henry Frankenstein (flashback) (uncredited)

Harry Cording as Mob Leader (uncredited)

George Eldredge as Constable (uncredited)

Dwight Frye as Villager at Meeting / Grave Robber (flashback) (uncredited)

Lawrence Grant as Mayor (uncredited)

Otto Hoffman as Villager (uncredited)

Brandon Hurst as Hans, Villager at Council Meeting (uncredited)

Michael Mark as Councilman (uncredited)

Jimmy Phillips as Boy Playing Indian (uncredited)

William Smith as Boy (uncredited)

Ernie Stanton as Constable (uncredited)

Julius Tannen as Sektal (uncredited)

Harry Tenbrook as Villager at Hearing (uncredited)

Glen Walters as Mother of Hungry Children (uncredited)

Janet Warren as Goose-herd (uncredited)

Teddy Infuhr as Boy (uncredited)