Masahiro Tabuchi (Masahiro Tabuchi, March 13, 1967-) is a Japanese AV actor, veteran old man JAV Pornstar, health instructor, and YouTuber.

He debuted as a Japanese AV Pornstar in 1990.

He is the former chairman of the Japan AV Actors Association (currently the association itself does not exist).

There are two notations depending on the work, “Masahiro Tabuchi 田渕正浩” and “Masahiro Tabuchi 田淵正浩”.

He has appeared not only in adult videos but also in general works. His stage name when he appeared in a general work was Masahiro Kobayashi.

田淵 正浩（たぶち まさひろ・1967年3月13日 – ）は、日本のAV男優、健康指導士、YouTuber。元日本AV男優協会（現在は会そのものが存在していない）会長。「田渕正浩」「田淵正浩」と、作品によって二通りの表記がある。アダルトビデオだけでなく一般作品にも出演している。一般作品出演時の芸名は小林政宏。