American Pie is a 1999 American coming-of-age teen sex comedy film directed and co-produced by Paul Weitz and written by Adam Herz. The film's main ensemble cast includes Jason Biggs, Chris Klein, Alyson Hannigan, Natasha Lyonne, Thomas Ian Nicholas, Tara Reid, Mena Suvari, Eddie Kaye Thomas, and Seann William Scott, with Eugene Levy, Shannon Elizabeth, Chris Owen, and Jennifer Coolidge in notable supporting roles. The story follows a group of high school classmates who make a pact to lose their virginity before they graduate.

After the success of Wes Craven's horror teen film Scream (1996), Herz began developing the script for American Pie, originally titled Untitled Teenage Sex Comedy That Can Be Made For Under $10 Million That Most Readers Will Probably Hate But I Think You Will Love. A bidding war between major film studios ensued, and Universal Pictures won the film's rights in 1998. First-time directors Chris and Paul Weitz were attached as directors for the film, although only Paul was credited. Under a new title of Great Falls, filming took place from July to September 1998. Despite receiving an NC-17 rating from the Motion Picture Association of America (MPAA), edits were made to secure an R rating. The film's title was later changed to American Pie.

Released theatrically by Universal on July 9, 1999, in the United States, American Pie initially received mixed reviews from critics, who were polarized on the raunchy humor but praised the performances. Nonetheless, the film was a box office success, grossing $235.5 million worldwide on a $10 million budget. American Pie revived the teen sex comedy genre for the late 1990s. The film's success also spawned a franchise, including three theatrical sequels American Pie 2, American Wedding, and American Reunion, and five direct-to-video film series American Pie Presents, consisting of Band Camp, The Naked Mile, Beta House, The Book of Love, and Girls' Rules.