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. It is the first film in the American Pie theatrical series and stars an ensemble cast that includes Jason Biggs, Chris Klein, Alyson Hannigan, Natasha Lyonne, Thomas Ian Nicholas, Tara Reid, Mena Suvari, Eddie Kaye Thomas, Seann William Scott, Eugene Levy, Shannon Elizabeth, and Jennifer Coolidge. The film's story centers on a group of five classmates who attend the fictional East Great Falls High School. The youths make a pact to lose their virginity before their high school graduation.

The film's title refers to a scene in which the protagonist is caught masturbating with a pie after being told that third base feels like "warm apple pie". 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."

The film was a box-office hit and spawned three direct sequels: American Pie 2, American Wedding, and American Reunion. In 2017, Scott said in an interview that the fourth film probably had not made enough at the domestic box office to warrant another film. In addition to the primary American Pie saga, there are five direct-to-DVD spin-off films bearing the title American Pie Presents: Band Camp, The Naked Mile, Beta House, The Book of Love, and Girls' Rules.