The film's producers, Michael Wilson and Barbara Broccoli, said they were "delighted" that Madonna was on board.
Filming has started
There was even a rumour that Madonna would have a small part in the film, but her spokeswoman has denied it.
Madonna joins a long line of music stars who've sung theme tunes for James Bond films. Old timers like Paul McCartney, Tom Jones, Tina Turner and even Sheryl Crow have recorded songs for 007.
Die Another Day is the 20th James Bond movie. Filming started in January this year, with Pierce Brosnan playing the British spy for the fourth time.