Koichi Tanaka (born October 20, 1971) is a Japanese mixed martial artist. He competed in the Featherweight division.
|- | Win | align=center| | Manabu Kano | Submission (rear-naked choke) | Deep: Osaka Impact | | align=center| 2 | align=center| 1:50 | Osaka, Japan | |- | Loss | align=center| 2âÂÂ11âÂÂ1 | Yuichi Miyagi | Decision (unanimous) | Pancrase: Rising 1 | | align=center| 2 | align=center| 5:00 | Osaka, Japan | |- | Loss | align=center| 2âÂÂ10âÂÂ1 | Kenji Takeshige | Submission (toe hold) | Pancrase: Blow 8 | | align=center| 2 | align=center| 2:38 | Osaka, Japan |<small>Lightweight bout.</small> |- | Loss | align=center| 2âÂÂ9âÂÂ1 | Hiroshi Komatsu | Decision (unanimous) | | | align=center| 2 | align=center| 5:00 | Osaka, Japan |<small>Bantamweight bout.</small> |- | Loss | align=center| 2âÂÂ8âÂÂ1 | Akitoshi Tamura | Decision (unanimous) | | | align=center| 2 | align=center| 5:00 | Tokyo, Japan | |- | Loss | align=center| 2âÂÂ7âÂÂ1 | Makoto Ishikawa | Decision (unanimous) | | | align=center| 2 | align=center| 5:00 | Tokyo, Japan |<small>Return to Featherweight.</small> |- | Loss | align=center| 2âÂÂ6âÂÂ1 | Yoshihiro Fujita | Technical Submission (armbar) | | | align=center| 1 | align=center| 3:58 | Osaka, Japan |<small>Bantamweight debut.</small> |- | Loss | align=center| 2âÂÂ5âÂÂ1 | Chikara Miyake | Submission (rear-naked choke) | | | align=center| 1 | align=center| 2:16 | Kadoma, Osaka, Japan | |- | Loss | align=center| 2âÂÂ4âÂÂ1 | Yohei Nanbu | Decision (majority) | | | align=center| 2 | align=center| 5:00 | Setagaya, Tokyo, Japan |<small>Return to Featherweight.</small> |- | Loss | align=center| 2âÂÂ3âÂÂ1 | Isao Tanimura | Decision (majority) | | | align=center| 2 | align=center| 5:00 | Setagaya, Tokyo, Japan |<small>Welterweight debut.</small> |- | Win | align=center| 2âÂÂ2âÂÂ1 | Patrick Madayag | Submission (rear-naked choke) | SB 10: SuperBrawl 10 | | align=center| 1 | align=center| 10:34 | Guam | |- | Loss | align=center| 1âÂÂ2âÂÂ1 | Jutaro Nakao | Submission (triangle choke) | | | align=center| 1 | align=center| 3:56 | Setagaya, Tokyo, Japan |<small>Return to Lightweight.</small> |- | Draw | align=center| 1âÂÂ1âÂÂ1 | Masato Fujiwara | Draw | | | align=center| 2 | align=center| 5:00 | Tokyo, Japan |<small>Featherweight debut.</small> |- | Loss | align=center| 1âÂÂ1 | Tetsuji Kato | Technical Submission (armbar) | | | align=center| 1 | align=center| 1:01 | Tokyo, Japan | |- | Win | align=center| 1âÂÂ0 | Tae Yoon Han | Submission (rear-naked choke) | CMA: Octagon Challenge | | align=center| 1 | align=center| 0:38 | Nagoya, Aichi, Japan |