Kentaro Otani (大谷健太郎 Otani Kentaro) (born 1965 in Kyoto, Japan) is a Japanese filmmaker.
Otani graduated from Tama Art University where he attended a workshop in 8mm film production. While a student he made an 8mm film called Ao Midori (lit. Blue Green) which won him an award at the 1988 Pia Film Festival. He continued making 8mm films after graduating as well as holding down a day job at a production company making company PR videos. In 1991 his film Watashi to Tanin ni natta Kare wa took home 3 awards at that year's PFF and was the most popular film shown. He then spent several years on his debut feature film, 1999's Avec Mon Mari.
-  Avec Mon Mari (screenwriter, director)
-  Travail (screenwriter, director)
-  30 Lies or So (screenwriter, director)
-  Nana (screenwriter, director)
-  Rough (director)
-  Nana 2 (screenwriter, director)