Charlton Heston
Maj. Bernard R. 'Barney' Benson
Julie Adams
Dr. Kay Lambert
William Demarest
John
Tim Hovey
Cadet Thomas 'Tiger' Flaherty
Nana Bryant
Mother Redempta
Tim Considine
Cadet Lt. Gerald Hibler
Sal Mineo
Cadet Col. Sylvester Dusik
Milburn Stone
Maj. Gen. Wilton J. Ramsey
Mary Field
Sister Mary Theresa
Joey D. Vieira
Cadet Cpl. Scawalski (as Donald Keeler)
Gary Pagett
Cadet Lt. Molony
Don Haggerty
Harold Hibler
David Janssen
Young Lieutenant
Richard H. Cutting
Monsignor Collins
Sue George
Nancy (uncredited)
Steven Benson
Cadet
Madge Blake
Woman at Airport