Fantasia is a 1940 American animated musical anthology film produced by Walt Disney Productions, with story direction by Joe Grant and Dick Huemer and production supervision by Walt Disney and Ben Sharpsteen. It consists of eight animated segments set to pieces of classical music conducted by Leopold Stokowski, seven of which are performed by the Philadelphia Orchestra. Music critic and composer Deems Taylor acts as the film's Master of Ceremonies who introduces each segment in live action.

Disney settled on the film's concept in 1938 as work neared completion on The Sorcerer's Apprentice, originally an elaborate Silly Symphony cartoon designed as a comeback role for Mickey Mouse, who had declined in popularity. As production costs surpassed what the short could earn, Disney decided to include it in a feature-length film of multiple segments set to classical pieces with Stokowski and Taylor as collaborators. The soundtrack was recorded using multiple audio channels and reproduced with Fantasound, a pioneering sound system developed by Disney and RCA that made Fantasia the first commercial film shown in stereo and a precursor to surround sound.

Fantasia was first released as a theatrical roadshow that was held in 13 cities across the U.S. between 1940 and 1941 by RKO Radio Pictures; the first began at the Broadway Theatre in New York City on November 13, 1940. While acclaimed by critics, it failed to make a profit owing to World War II's cutting off distribution to the European market, the film's high production costs, and the expense of building Fantasound equipment and leasing theatres for the roadshow presentations. Since 1942, the film has been reissued multiple times by RKO Radio Pictures and Buena Vista Distribution with its original footage and audio being deleted, modified, or restored in each version. When adjusted for inflation, Fantasia is the 23rd highest-grossing film of all time in the U.S.

The Fantasia franchise has grown to include video games, Disneyland attractions, and a live concert series. A sequel, Fantasia 2000, co-produced by Walt's nephew Roy E. Disney, was released in 1999. Fantasia has grown in reputation over the years and is now widely acclaimed as one of the greatest animated films of all time; in 1998, the American Film Institute ranked it as the 58th greatest American film in their 100 Years...100 Movies and the fifth greatest animated film in their 10 Top 10 list. In 1990, Fantasia was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant."