Young Dr. Kildare

Lionel Barrymore

Dr. Leonard Gillespie

Lew Ayres

Dr. James Kildare

Lynne Carver

Alice Raymond

Nat Pendleton

Joe Wayman

Jo Ann Sayers

Barbara Chanler

Samuel S. Hinds

Dr. Stephen Kildare

Emma Dunn

Mrs. Martha Kildare

Walter Kingsford

Dr. P. Walter Carew

Truman Bradley

Jack Hamilton

Monty Woolley

Dr. Lane-Porteus

Pierre Watkin

Mr. Robert Chanler

Nella Walker

Mrs. Chanler

Murray Alper

Blue Swan Waiter (uncredited)

Don 'Red' Barry

Dr. Collins (uncredited)

Granville Bates

Harry Cook (uncredited)

Barbara Bedford

Nurse (uncredited)

Margaret Bert

Little Boy's Mother (uncredited)

Marie Blake

Miss Sally Green (uncredited)

Virginia Brissac

Boardinghouse Landlady (uncredited)

John Butler

Coronary Patient (uncredited)