Shrek is a 2001 American animated fantasy comedy film loosely based on the 1990 children's picture book Shrek! by William Steig. Directed by Andrew Adamson and Vicky Jenson, and written by Ted Elliott, Terry Rossio, Joe Stillman, and Roger S. H. Schulman, it is the first installment in the Shrek film series. The film stars Mike Myers, Eddie Murphy, Cameron Diaz, and John Lithgow. In the film, an embittered ogre named Shrek (Myers) finds his home in the swamp overrun by fairy tale creatures banished by the obsessive ruler Lord Farquaad (Lithgow). With the help of Donkey (Murphy), Shrek makes a pact with Farquaad to rescue Princess Fiona (Diaz) in exchange for regaining control of his swamp.

After purchasing the rights to Steig's book in 1991, Steven Spielberg sought to produce a traditionally-animated film adaptation, but John H. Williams convinced him to bring the project to the newly founded DreamWorks Pictures in 1994. Jeffrey Katzenberg, along with Williams and Aron Warner, began development on Shrek in 1995, immediately following the studio's purchase of the rights from Spielberg. Chris Farley was cast as the voice for the title character, recording most of the required dialogue, but died in 1997 before his work on the film was finished; Myers was hired to replace him, and gave Shrek his Scottish accent. The film was initially intended to be created using motion capture, but after poor test results, the studio hired Pacific Data Images to complete the final computer animation. Shrek parodies other fairy tale adaptations, primarily animated Disney films.

Shrek premiered at the Mann Village Theatre In Westwood, and was later shown at the 2001 Cannes Film Festival, where it competed for the Palme d'Or, making it the first animated film since Disney's Peter Pan (1953) to be chosen to do so. The film was theatrically released by DreamWorks Pictures in the United States on May 18, 2001, and grossed over $492 million worldwide, becoming the fourth highest-grossing film of 2001. It was widely praised by critics for its animation, voice performances, soundtrack, writing and humor, which they noted catered to both adults and children. Shrek was named one of the top 10 films of 2001 by the American Film Institute, the first animated film to be listed, and won numerous accolades including the BAFTA Award for Best Adapted Screenplay and the inaugural Academy Award for Best Animated Feature.

The film's major success helped establish DreamWorks Animation as a competitor to Pixar in feature film computer animation. Three sequels have been released—Shrek 2 (2004), Shrek the Third (2007), and Shrek Forever After (2010)—along with two spin-off films—Puss in Boots (2011) and Puss in Boots: The Last Wish (2022)—with other productions, notably Shrek 5, in development. It is also regarded as one of the most influential animated films of the 2000s and one of the greatest animated films ever made. The United States Library of Congress selected Shrek for preservation in the National Film Registry in 2020, becoming the first animated film of the 21st century to be preserved.