Stadium: Court 10 Round: 54 Ground: Hardcourt outdoor
| ITF Japan F5 | 2015/05/30 01:00 | Issei Okamura v Shota Iino | 6-3,2-6,6-4 |
| ITF M15 Kashiwa | 2019/04/04 01:00 | Issei Okamura v Jumpei Yamasaki | 3-6,2-6 |
| ITF M15 Kashiwa | 2019/04/02 05:50 | Taisei Ichikawa v Issei Okamura | 7-5,5-7,5-7 |
| ITF M15 Tsukuba | 2019/03/27 03:25 | Issei Okamura v Naoki Tajima | 3-6,4-6 |
| ITF M15 Kofu | 2019/03/22 02:00 | Issei Okamura v Ryota Tanuma | 4-6,2-6 |
| ITF M15 Kofu | 2019/03/21 02:00 | Takuya Kumasaka v Issei Okamura | 1-6,2-6 |
| ITF M15 Kofu | 2019/03/19 02:50 | Aoran Wang v Issei Okamura | 2-6,6-4,4-6 |
| ITF M15 Nishi-Tokyo | 2019/03/13 05:25 | Rimpei Kawakami v Issei Okamura | 6-2,6-1 |
| ITF M15 Nishi-Tokyo | 2019/03/12 01:00 | Issei Okamura v Hikaru Shiraishi | 6-2,6-3 |
| ITF M25 Matsuyama | 2019/04/08 01:00 | Shota Iino v Masayoshi Ono | 7-6,6-0 |
| ITF Japan F6 | 2018/04/10 04:45 | Shota Iino v Ryota Tanuma | 2-6,2-6 |
| ITF Japan F6 Qual | 2015/06/07 03:30 | Ryota Kishi v Shota Iino | 7-5,3-6,6-3 |
| ITF Japan F5 | 2015/05/30 01:00 | Issei Okamura v Shota Iino | 6-3,2-6,6-4 |