American Chopper is an American reality television series that airs on Discovery Channel, produced by Pilgrim Films & Television. The series centers on Paul Teutul Sr. (frequently called Senior), and his son Paul Teutul Jr. (also known as Paulie or simply Junior), who manufacture custom chopper-style motorcycles. Orange County Choppers is in Newburgh, New York. The contrasting work and creative styles of the father-and-son team and their resulting verbal arguments were the series' hallmark until 2008 when an explosive argument led to Paul Jr.'s termination and departure to start a competing chopper company, Paul Jr. Designs.

The series originally aired on Discovery Channel beginning in March 2003. In December 2007, the series moved to Discovery's sister channel TLC, starting off with an 18-hour marathon. Its first TLC season premiered in January 2008. Season 6 began in April 2009 but the series was canceled by TLC in February 2010. In July 2010, TLC announced that the Teutuls would return in a new series, American Chopper: Senior vs. Junior. Senior vs. Junior premiered on TLC but was soon moved to Discovery halfway through the first season. Discovery Channel announced that the show would end with "The Chopper Live: The Revenge" show on December 11, 2012 after 10 years.