Koichi Wajima (輪島 功一, born 21 April 1943) is a Japanese former professional boxer who was the undisputed light-middleweight champion.

He and his family moved to Shibetsu, Hokkaidō, but barely managed to make a living, Wajima was put up for adoption.

After graduating from middle school, he traveled to Tokyo, where he worked briefly as a truck driver before joining the Misako Boxing Gym.

He got a rematch with Albarado 7 months later, on January 21, 1975, and managed to avenge his loss with a 15-round decision win to regain the Lineal, WBC and WBA titles.

Wajima lost to Jose Manuel Duran in his first defense, losing the world title for the third time in his career.

He fought his final match In June, 1977, challenging Eddie Gazo for the WBA super welterweight title, but lost by 11th-round KO.