During an interview with BBC Breakfast, the journalist and presenter heaped praise on the film, which has received nominations for Best Director (Ron Howard), Best Picture, Best Actor (Frank Langella), Best Adapted Screenplay and Best Film Editing.
The movie, adapted from the play of the same name, is based on Sir David's interviews with the former US President over the Watergate scandal.
Frost said that the movie is "about 10% fiction" and praised Howard for bringing it together.
Speaking of Langella's performance, he said: "I really hope he wins the Oscar for that fantastic performance sustained right through. He started on stage and he said he was so tense that instead of talking to someone when he was off stage for ten minutes, he'd go to the back of the stage, somewhere dark, so he kept in character.
"And then when the stage manager came over to him, he had to say: 'Mr President, you're required on stage.'"
> Click here to read our review of Frost/Nixon