Musa (Korean: 무사; Hanja: 武士; lit. The Warrior), released as both The Warrior and The Ultimate Warrior in English-speaking countries, is a 2001 South Korean epic action drama film directed by Kim Sung-su, starring Jung Woo-sung, Ahn Sung-ki, Joo Jin-mo and Chinese actress Zhang Ziyi. The semi-historical story follows the adventures of a Korean peace delegation as they try to get back to Korea through the inhospitable deserts of northern China.

The film is regarded as being one of the biggest motion pictures in the history of South Korean cinema. At the time of its production, its budget was the largest ever for a Korean film. It features a high degree of historical accuracy in period costumery, props, settings and most unusually, language; that is, everyone speaks in their native tongues or through an interpreter conversant in a lingua franca. The film was the eighth highest-grossing film of 2001 with over two million tickets sold.