Hanamichi Sakuragi is a delinquent outcast and member of a gang. Sakuragi, being very unpopular with girls, has been rejected by them 50 times. In his first year at Shohoku High School, he finds out that Haruko Akagi is the girl of his dreams, and is happy when she is not scared of him like all the other girls he has asked out.

Haruko Akagi, who recognizes Sakuragi's athleticism, introduces him to the Shohoku basketball team. Sakuragi was reluctant to join the team at first because he had no previous background in any sports and thought that basketball was a game for losers (also because the 50th girl rejected him for a basketball player). Sakuragi, despite his immaturity and hot temper, proves to be a natural athlete with potential and joins the team in order to impress Haruko and prove that he is worthy of her. Later on, Sakuragi realizes that his love for the sport equals that of his crush on Haruko. Kaede Rukawa — Sakuragi's bitter rival (both in basketball and because Haruko has a crush, albeit a one-sided one, on Rukawa), the star rookie and a "girl magnet" — joins the team at the same time. Hisashi Mitsui, an ex-junior high school MVP, and Ryota Miyagi, a short but fast player, both also rejoin the team and together these four struggle to complete team captain Takenori Akagi's dream of making Shohoku the national champion. Together, these misfits gain publicity and the once little known Shohoku basketball team becomes an all-star contender in Japan.