Yū Koyama (小山ゆう Koyama Yū?, born 20 February 1948 in Ogasa, Shizuoka) is a Japanese manga artist. After graduating from the University of Shizuoka he moved to Tokyo and in 1968 took a job with Saito Productions, the company run by mangaka Takao Saitō. In 1971 he worked with Kazuo Koike at Studio Ship.
He debuted in Shonen Sunday in 1978 with Ore wa Chokkaku.
He has won multiple awards in the manga field, winning the Shogakukan Manga Award twice, once in 1977 for Ganbare Genki and again in 1998 for Azumi. Azumi also won an Excellence Award at the 1997 Japan Media Arts Festival.
- "小学館漫画賞：歴代受賞者" (in Japanese). Shogakukan. Retrieved 2007-08-19.
- Gifford, Kevin. "Azumi". (November 2006) Newtype USA. p. 154.