Ong-Bak: Muay Thai Warrior (Thai: องค์บาก; IPA: [ɔːŋbaːk]) is a 2003 Thai action film. It was directed by Prachya Pinkaew, featured stunt choreography by Panna Rittikrai and starred Tony Jaa. Ong-Bak proved to be Jaa's breakout film, with the actor hailed internationally as the next major martial-arts star. Jaa went on to star in Tom-Yum-Goong (called The Protector in the US and Warrior King in the UK) and is directing a sequel to Ong-Bak, Ong-Bak 2.

Ong-Bak is an unabashed "Hey, look at what I can do!" action moviestarring the main character's martial abilities. Its onrush of chase scenes, hand-to-hand combat and acrobatics, sometimes shown multiple times from different angles,drew notice for its quality, inventive moves and lack of CGI and wire-fu.