The Wizard of Oz is a 1939 musical fantasy film produced by Metro-Goldwyn-Mayer. It is based on L. Frank Baum's turn-of-the-century children's story The Wonderful Wizard of Oz, in which a resourceful American girl is snatched up by a Kansas tornado and deposited in a fantastic land of witches, a talking scarecrow, a cowardly lion, and more. It made stars out of its cast members: Judy Garland, Frank Morgan, Ray Bolger, Jack Haley, Bert Lahr, Billie Burke and Margaret Hamilton. It also featured a cast of uncredited small actors in the roles of the Munchkins, including Jerry Maren in the Lollipop Guild and Meinhardt Raabe as the Munchkin Coroner. While by far not the earliest feature film produced in Technicolor (the first of which was released in 1917), The Wizard of Oz made conspicuous use of the now-perfected technology; the film's Kansas bookend sequences are in sepia-toned black-and-white, while the Oz scenes are in full three-strip Technicolor. The film is scheduled for theatrical re-release in the UK on 15th December 2006.

In January 1938, MGM bought the rights to the book. The script was completed on October 8, 1938 (following numerous rewrites). Filming started on October 13, 1938 and was completed on March 16, 1939. The film premiered on August 12, 1939, and went into general release on August 25.

The movie's script was adapted by Noel Langley, Florence Ryerson, and Edgar Allan Woolf. Several people assisted with the adaptation without official credit: Irving Brecher, William H. Cannon, Herbert Fields, Arthur Freed, Jack Haley, E.Y. Harburg, Samuel Hoffenstein, Bert Lahr, John Lee Mahin, Herman J. Mankiewicz, Jack Mintz, Ogden Nash, and Sid Silvers. It was directed by Victor Fleming, Richard Thorpe (uncredited), George Cukor (uncredited), and King Vidor (uncredited). Costume design was by Adrian.

Music and Lyrics were by Harold Arlen and E.Y. "Yip" Harburg, who won Academy Awards for Best Music, Original Score and Best Music, Song for "Over the Rainbow".