The confirmation came in the form of a Twitpic she posted to Twitter, which shows a cover page for the song credited to Adele -- as A. Adkins -- and Paul Hepworth, who co-wrote her most popular tune, "Rolling in the Deep."
Rumors floated around for weeks that Adele was the voice behind the theme, but there had been no official word until now.
The song will be available on Adele's official site starting Friday, which is also the 50th anniversary of the release of "Dr. No," the first Bond movie. The track is available for pre-order at iTunes starting Monday.
"Skyfall" debuts in Britain Oct. 26 and in the U.S. Nov. 9. The film is Daniel Craig's third as James Bond. The film's other stars include Javier Bardem, Albert Finney, Ralph Fiennes and Naomie Harris.
The Associated Press contributed to this report.