Margaret O'Brien as Mike

José Iturbi as José Iturbi

June Allyson as Barbara Ainsworth

Jimmy Durante as Andrews

Marsha Hunt as Rosalind

Hugh Herbert as Uncle Ferdinand

Harry Davenport as Doctor

Marie Wilson as Marie

Larry Adler as Larry

Ben Lessy as Kickebush

Connie Gilchrist as Travelers Aid Woman

Katherine Balfour as Elsa

Helen Gilbert as Helen

Madeleine Lebeau as Jane (as Madeleine LeBeau)

Ethel Griffies as Mrs. McGuff

Mary Parker as Anita

Eddie Jackson as Singer

Jack Roth as Drummer

Willie Best as Red Cap (uncredited)

Bess Flowers as Concertgoer (uncredited)

Byron Foulger as Mr. Perkins (uncredited)