Among the 18 films competing for the award, the favorite had been George Clooney's "Good Night, and Good Luck," the BBC said Sunday.
Clooney and his co-writer, Grant Heslov, won for best screenplay. "Good Night, and Good Luck" star David Strathairn won the prize for best actor, for his performance as legendary CBS newsman Edward R. Murrow.
The best actress award went to Italian Giovanna Mezzogiorno for "La Bestia nel Cuore" and French actress Isabelle Huppert won a special Lion for outstanding contribution to cinema.
The Silver Lion went to director Philippe Garrel for "Les Amants réguliers," and U.S. director Abel Ferrara won the Jury Grand Prix for "Mary," about an actress who is haunted by Mary Magdalene after having playing her on screen.