Friend (친구 Chin-gu) is a 2001 South Korean film directed by Kwak Kyung-taek. At one time, it was the highest-grossing South Korean movie of all time, but has since been surpassed by Silmido, Taegukgi , The King and the Clown , Speedy Scandal and The Host. It has since been remade into a TV series by MBC. A part of the music was composed by Belgian composer Luc Baiwir.^{[citation needed]}

This film is the director's experience about his friends, a semi-autobiography set in his hometown, Busan, and the actors speak with a strongly accented Busan dialect. The film changed the public images of Jang Dong-gun and Yu Oh-sung; previously, Jang had been famous for romantic comedies and Yu had appeared in movies with mostly cult interest.

The film follows the lives of four childhood friends: Joon-seok, the leader of the group and whose father is a powerful mob boss; Dong-su, whose father is an undertaker; class clown Jung-ho; and Sang-taek, who was an exemplary student. As children they play together, sell sexually explicit pictures cut from a magazine, and wonder if a South Korean Olympic swimmer could outrace a sea turtle. Jung-ho also showed the rest of them a VCR that his mother had, and this film he found on it. It turns out to be a pornographic movie, and the boys are entranced while arguing over what a "menstruation" was, with them believing that it was the word that adults used to describe the "vagina".