American Ninja Warrior (sometimes abbreviated as ANW) is an American sports entertainment reality show based on the Japanese television reality show Sasuke, which also serves as a successor of American Ninja Challenge. It features a set of obstacle courses in various cities, which contestants attempt to conquer. The obstacle courses are divided into Qualifiers courses, Semifinals courses, and a four-part Finals course which is based at Las Vegas Strip (sometimes called Mount Midoriyama). The contestant who finishes all the courses in the fastest time wins a cash prize of $1,000,000. Starting with season 10, if one remaining contestant fails on any of Finals course parts, but has completed it more than the others in the fastest time, he wins a consolatory $100,000 prize. The show is hosted by Matt Iseman (the show's moderator) and Akbar Gbaja-Biamila. To date, only Isaac Caldiero, Drew Drechsel, and Vance Walker have won the main cash prize. Furthermore, Geoff Britten and Daniel Gil are the only two runners-up who have achieved Total Victory.

The series premiered on December 12, 2009, on cable channel G4. For the first three seasons, the show only screened a single qualifies and semifinals course while the top contestants travelled to Japan to compete at the Sasuke seasons' finals course. In 2012, the show changed its format by creating the fixed Finals course in Las Vegas and moved to NBC for its fourth season. In 2020, following COVID-19 restrictions, the show abolished the usual format and filmed a shorter season in St. Louis studio with no live audience. Production for the 13th season resumed in traditional format. In 2023, the series was renewed for 15th and 16th seasons, which are filmed simultaneously. The 15th season premiered on June 5, 2023, while the 16th season would air next summer.