Sunset Boulevard is a 1950 American noir film directed and co-written by Billy Wilder. It was named after the boulevard that runs through Los Angeles and Beverly Hills, California.

The film stars William Holden as down-on-his-luck screenwriter Joe Gillis, and Gloria Swanson as Norma Desmond, a faded movie star who draws Gillis into her fantasy world in which she dreams of making a triumphant return to the screen. Erich von Stroheim, Nancy Olson, Fred Clark, Lloyd Gough and Jack Webb play supporting roles. Director Cecil B. DeMille and gossip columnist Hedda Hopper play themselves, and the film includes cameo appearances by leading silent film figures Buster Keaton, H. B. Warner and Anna Q. Nilsson.

Praised by many critics when first released, Sunset Boulevard was nominated for eleven Academy Awards and won three. It is widely accepted as a classic, often cited as one of the most noteworthy films of American cinema. Deemed "culturally, historically, or aesthetically significant" by the U.S. Library of Congress in 1989, Sunset Boulevard was included in the first group of films selected for preservation in the National Film Registry. In 1998, it was ranked number twelve on the American Film Institute's list of the 100 best American films of the 20th century, and number 16 on their 10th Anniversary list in 2007.