Alyson Hannigan, Tara Reid, Shannon Elizabeth, Mena Suvari and Jason Biggs by Mark Seliger for Rolling Stone Magazine

American Pie is a 1999 American teen sex comedy film written by Adam Herz and directed by brothers Paul and Chris Weitz, in their directorial film debut. It is the first film in the American Pie theatrical series. The film was a box-office hit and spawned three direct sequels: American Pie 2 (2001), American Wedding (2003), and American Reunion (2012). The film concentrates on five best friends (Jim, Kevin, Oz, Finch, and Stifler) who attend East Great Falls High. With the exception of Stifler (who has already lost his virginity), the guys make a pact to lose their virginity before their high school graduation. The title is borrowed from the song of the same name and refers to a scene in the film, in which the protagonist is caught masturbating with a pie after being told that third base feels like "warm apple pie". Writer Adam Herz has stated that the title also refers to the quest of losing one's virginity in high school, which is as "American as apple pie."

In addition to the primary American Pie saga, there are four direct-to-DVD spin-off films bearing the title American Pie Presents: Band Camp (2005), The Naked Mile (2006), Beta House (2007), and The Book of Love (2009).

In response to the success of American Reunion, a fifth theatrical film, under the working title American Pie 5 was announced on August 4, 2012. In August 2017, Seann William Scott said in an interview that the fourth film probably had not made enough at the domestic box office to warrant another film.