Joint Security Area (Korean: 공동경비구역 JSA) is a 2000 South Korean mystery thriller film directed and co-written by Park Chan-wook and based on the novel DMZ by Park Sang-yeon. It is Park Chan-wook's third film as director; as he largely disowned his first two films The Moon Is... the Sun's Dream (1992) and Trio (1997), Joint Security Area is frequently regarded as his first film with creative control, and Park himself prefers the film to be regarded as his directorial debut.

Starring Song Kang-ho, Lee Byung-hun and Lee Young-ae, Joint Security Area is set in the Korean Demilitarized Zone separating the countries of North Korea and South Korea and revolves around a fatal shooting incident involving soldiers from both sides, which leads the Neutral Nations Supervisory Commission to investigate and gradually unveil the unexpected truth.

The film was released theatrically on September 9, 2000 in South Korea where it became a major commercial success, launching Park's career and becoming the highest-grossing film in South Korean history until Friend surpassed it the following year. It was nominated for three Blue Dragon Film Awards, winning Best Film and Best Cinematography, and for thirteen Grand Bell Awards, winning Best Film, Best Actor for Song, Best Art Direction and Best Sound Effects.