溝口肇 (Mizoguchi Hajime) is a cellist and composer. He was born in Tokyo in 1960.

Mizoguchi started playing piano in 1963 and cello in 1971. From 1978 to 1985 at Tokyo university of art he majored in violoncello. While at school, he started playing the cello with Japanese pop‑singer and working as a studio musician for radio, TV, films, and albums.

In 1982, at the age of 22, he had a serious traffic accident. This is what made him start composing.

In 1986, he released his first album, «Half inch dessert». For this recording, he worked as composer, arranger, and performer. From that time on, he has released more than 20 albums including motion picture soundtracks, has performed in many concerts with his own or ensembles, has produced various musicians, and soon. By the late 1980s, he was generally recognized as one of the leading musicians in Japan.

His compositions include the soundtrack to the animated feature film «Jin‑Roh: The Wolf Brigade» and half of the «Texhnolyze» Soundtrack. He is married to composer Yoko Kanno, with whom he collaborated on the soundtracks for «Please Save My Earth» and «Vision of Escaflowne».