Round: 25 Ground: Synthetic outdoor
| ITF Japan F8 | 2015/06/24 01:10 | Oku, Hiromasa v Katayama, Sho | 6-7,0-6 |
| ITF Japan F6 | 2016/06/02 01:00 | Oku, Hiromasa v Kibi, Yuya | 3-6,2-6 |
| ITF Japan F6 | 2016/05/31 01:00 | Niki, Takuto v Oku, Hiromasa | 2-6,3-6 |
| ITF Guam F1 | 2016/05/24 02:00 | Oku, Hiromasa v Takeshima, Shunrou | 3-6,2-6 |
| ITF Turkey F19 | 2016/05/13 09:20 | Sieber, Marc v Oku, Hiromasa | 6-0,6-3 |
| ITF Turkey F19 | 2016/05/11 13:00 | Oku, Hiromasa v Statzberger, Thomas | 6-3,6-4 |
| ITF Turkey F18 | 2016/05/04 08:00 | Oku, Hiromasa v Yuksel, Anil | 3-6,2-6 |
| Turkey F17, Singles Qualifying | 2016/04/26 11:20 | Altug Celikbilek v Oku, Hiromasa | 6-4,2-6,7-6 |
| ITF Japan F5 | 2016/04/08 01:00 | Oku, Hiromasa v Kibi, Yuya | 2-6,4-6 |
| ITF Japan F6 | 2016/06/01 01:00 | Katayama, Sho v Yasutaka Uchiyama | 4-6,3-6 |
| ITF Japan F6 | 2016/05/31 01:00 | Katayama, Sho v Nagao, Katsuki | 3-6,6-4,6-3 |
| ITF Guam F1 | 2016/05/27 00:00 | Baughman, Deiton v Katayama, Sho | 6-4,6-4 |
| ITF Guam F1 | 2016/05/25 01:35 | Oh, Seong-Gook v Katayama, Sho | 4-6,1-6 |
| ITF Guam F1 | 2016/05/24 00:00 | Goh, Steven v Katayama, Sho | 0-6,4-6 |
| ITF India F2 | 2016/05/06 04:30 | Katayama, Sho v Sidharth Rawat | 6-2,3-6,3-6 |
| ITF India F2 | 2016/05/05 04:00 | Susanto, David Agung v Katayama, Sho | 4-6,4-6 |
| ITF India F2 | 2016/05/04 04:00 | Bava, Haadin v Katayama, Sho | 6-3,5-7,0-6 |