- Gregory Peck
- Monsignor Hugh O'Flaherty
- Christopher Plummer
- Col. Herbert Kappler
- John Gielgud
- Pope Pius XII
- Raf Vallone
- Father Vittorio
- Kenneth Colley
- Capt. Hirsch
- Walter Gotell
- Gen. Max Helm
- Barbara Bouchet
- Minna Kappler
- Julian Holloway
- Alfred West
- Angelo Infanti
- Father Morosini
- Olga Karlatos
- Francesca Lombardo
- Michael Byrne
- Reinhard Beck
- T.P. McKenna
- Reichsführer Heinrich Himmler
- Vernon Dobtcheff
- Count Langenthal
- John Terry
- Lt. Jack Manning
- Peter Burton
- Sir D'Arcy Osborne
- Phillip Hatton
- Lt. Harry Barnett
- Mark Lewis
- Cpl. Les Tate
- Fabiana Udenio
- Guila Lombardo
- Marne Maitland
- Papal Secretary
- Remo Remotti
- Rabbi Leoni
- Giovanni Crippa
- Simon Weiss
- Billy Boyle
- Paddy Doyle
- Itaco Nardulli
- Franz Kappler
- Cariddi McKinnon Nardulli
- Liesel Kappler
- Alessandra Cozzo
- Emilia Lombardo
- William Berger
- U.S. Intelligence Officer
- Edmund Purdom
- British Intelligence Officer / Epilogue Narrator (as Edmond Purdom)
- Gabriella D'Olive
- Mother Superior
- Cesarina Tacconi
- Pregnant Woman
- David Brandon
- SS Officer
- Sergio Nicolai
- Firing Squad Officer
- Bruno Corazzari
- Coalman
- Stelio Candelli
- O'Flaherty's Secretary
- Francesco Carnelutti
- Cameriere Segreto
- Greg Anthony
- Prisoner of War
- Angelo Boscariol
- Man at the opera
- Alberigo Donadeo
- Onlooker
- Gabriele Ferzetti
- Prince Mataeo
- Alfonso Giganti
- Nazi officer
- Giovanni Lombardo Radice
- Nazi Soldier