Round: 25 Ground: Hardcourt outdoor
| ITF Japan F8 | 2016/06/15 04:30 | Tanuma, Ryota v Katayama, Sho | 3-6,1-6 |
| ITF Japan F7 | 2016/06/09 01:00 | Watanuki, Yusuke v Tanuma, Ryota | 6-0,6-2 |
| ITF Japan F7 | 2016/06/06 01:00 | Tanuma, Ryota v Kai, Naoto | 6-4,6-3 |
| ITF Japan F6 | 2016/05/31 04:25 | Takeuchi, Kento (1987) v Tanuma, Ryota | 6-3,3-6,6-2 |
| ITF Spain F15 | 2016/05/27 16:05 | Struvay, Eduardo v Tanuma, Ryota | 6-4,6-2 |
| ITF Spain F15 Qual | 2016/05/23 10:20 | Tanuma, Ryota v Sebaoun, Leo Julien | 7-6,4-6,6-2 |
| ITF Spain F15 Qual | 2016/05/21 12:30 | Tanuma, Ryota v Alex M Pujolras | 6-0,6-1 |
| ITF Spain F14 | 2016/05/18 10:00 | Tanuma, Ryota v Jaume Munar | 6-4,2-6,5-7 |
| ITF Hong Kong F2 Qual | 2016/06/15 22:00 | Libietis, Mikelis v Onozawa, Arata | 6-4,7-6 |
| ITF Hong Kong F2 Qual | 2016/06/14 22:00 | Xia, Zihao v Onozawa, Arata | 4-6,2-6 |
| ITF Japan F7 | 2016/06/08 03:30 | Ito, Yuya v Onozawa, Arata | 6-4,6-1 |
| ITF Japan F7 | 2016/06/06 05:05 | Onozawa, Arata v Onishi, Ken | 6-4,6-7,6-0 |
| ITF Japan F6 | 2016/05/31 01:00 | Makoto Ochi v Onozawa, Arata | 6-2,6-3 |
| ITF China F7 | 2016/05/17 04:30 | Onozawa, Arata v Wei-De Lin | 3-6,3-6 |
| ITF China F6 | 2016/05/12 02:00 | Onozawa, Arata v Michael Geerts | 4-6,6-7 |
| ITF China F6 | 2016/05/10 04:20 | Ning, Yuqing v Onozawa, Arata | 3-6,7-5,4-6 |