Donald O'Connor
— Donald J. O'Connor
Gloria Jean
— Patricia Davis
Peggy Ryan
— Peggy
Robert Paige
— Johnny Hanley
Elyse Knox
— Alice Taswell
Samuel S. Hinds
— Jeremy Taswell
Robert Scheerer
— Bobby (as Bobby Scheerer)
Richard Stewart
— Genius
Elinor Donahue
— Muggsy
Florence Bates
— Mrs. Mary Davis
Ray Eberle
— Ray Eberle
Eddie Miller
— Leader, Eddie Miller's Bob Cats
Ben Carter
— Ben Carter - Choir Leader
Irving Bacon
— Jimmy, Malt Shop Proprietor
William Ruhl
— Producer
Alan Ward
— Producer
Jimmie Lucas
— Gardener
Lassie Lou Ahern
— Dancer (uncredited)
Dorothy Babb
— 'Jivin' Jacks and Jills' Member (uncredited)
Bobby Brooks
— Specialty Act (uncredited)
Roland Dupree
— 'Jivin' Jacks and Jills' Member (uncredited)
Bess Flowers
— Theatrical Party Member (uncredited)
Karen X. Gaylord
— Theatrical Party Member (uncredited)
Jean Inness
— Theatrical Party Member (uncredited)
Charles Marsh
— Theatrical Producer (uncredited)
Shirley Mills
— 'Jivin' Jacks and Jills' Member (uncredited)
Bert Moorhouse
— Theatrical Producer (uncredited)
Patsy O'Connor
— Genius' Dancing Partner (uncredited)
Tommy Rall
— 'Jivin' Jacks and Jills' Member (uncredited)
Emmett Vogan
— Theatrical Party Member (uncredited)