Gregory Peck
Capt. Horatio Hornblower R.N
Virginia Mayo
Lady Barbara Wellesley
Robert Beatty
Lt. William Bush
Moultrie Kelsall
Lt. Crystal
Terence Morgan
2nd Lt. Gerard
James Kenney
Midshipman Longley
James Robertson Justice
Seaman Quist
Denis O'Dea
RAdm. Sir Rodney Leighton
Richard Hearne
Polwheal (Hornblower's Batman)
Michael Dolan
Surgeon Gundarson
Stanley Baker
Mr. Harrison (Bosun)
Alan Tilvern
Hernandez
Alec Mango
El Supremo (Don Julian Alvarado)
Christopher Lee
Spanish Captain
John Witty
Capt. Entenza
Michael Goodliffe
Col. Caillard - POW Escort
Eugene Deckers
French Commandant
Ingeborg von Kusserow
Hebe (Lady Barbara's Maid)
Amy Veness
Mrs. McPhee (Hornblower's Housekeeper)
Kynaston Reeves
Adm. Lord Hood
Ronald Adam
Adm. McCartney
Chris Adcock
Crewman (uncredited)
Basil Bartlett
Capt. Elliott (uncredited)
André Belhomme
French Guard (uncredited)
David Birks
Crewman (uncredited)
Robert Cawdron
"Witch of Endor" French Mate (uncredited)
Diane Cilento
Maria Hornblower (voice) (uncredited)
Howard Connell
"Lydia" Seaman (uncredited)
Alexander Davion
Spanish Officer (uncredited)
Steve Donahue
Crewman (uncredited)
Patric Doonan
Seaman (uncredited)
Anthony Forwood
Lt. Woodford (uncredited)
Arthur Gomez
French Corvette Captain (uncredited)
Lindsay Hooper
Crewman (uncredited)
Richard Johnson
Macrae (uncredited)