Stadium: Court 12 Round: 25 Ground: Hardcourt outdoor
| ITF Japan F6 | 2018/04/10 03:10 | Kazuki Nishiwaki v Issei Okamura | 6-2,7-5 |
| ITF Singapore F1 | 2017/05/25 02:00 | Issei Okamura v Kazuki Nishiwaki | 6-7,1-6 |
| Challenger Jinan | 2024/08/18 12:35 | Charles Chen v Kazuki Nishiwaki | 5-7,6-3,6-3 |
| ITF M25 Taipei | 2024/08/08 03:30 | Kazuki Nishiwaki v Blake Ellis | 6-7,4-6 |
| ITF M25 Taipei | 2024/08/07 01:55 | Sidharth Rawat v Kazuki Nishiwaki | 3-6,2-6 |
| Challenger Astana | 2024/07/15 05:00 | Kazuki Nishiwaki v Antoine Ghibaudo | 3-6,3-6 |
| Challenger Astana | 2024/07/14 05:00 | Kazuki Nishiwaki v Nitin Kumar Sinha | 7-6,7-5 |
| ITF M15 Tokyo | 2024/07/11 02:00 | Kazuki Nishiwaki v Taiyo Yamanaka | 3-6,3-6 |
| ITF M15 Tokyo | 2024/07/10 07:15 | Kazuki Nishiwaki v Reiya Komagata | 6-3,6-1 |
| ITF M15 Hong Kong | 2024/06/20 02:00 | Tomohiro Masabayashi v Kazuki Nishiwaki | 7-5,6-1 |
| ITF M25 Taipei | 2024/08/04 02:00 | Jeffrey Hsu v Issei Okamura | 2-6,6-1,9-11 |
| ITF M15 Tokyo | 2024/07/08 01:00 | Yusuke Kusuhara v Issei Okamura | 6-3,6-4 |
| ITF M15 Nakhon Si Thammarat | 2024/07/05 02:00 | Issei Okamura v Adil Kalyanpur | 3-6,3-6 |
| ITF M15 Nakhon Si Thammarat | 2024/07/04 06:20 | Amit Vales v Issei Okamura | 3-6,3-6 |
| ITF M15 Nakhon Si Thammarat | 2024/07/03 02:00 | James Van Herzeele v Issei Okamura | 2-6,4-6 |
| ITF M15 Nakhon Si Thammarat | 2024/07/01 02:00 | Issei Okamura v Gabor Hornung | 6-4,2-6,10-6 |
| ITF M25 Luzhou | 2024/06/19 09:55 | Sheng Tang v Issei Okamura | 6-3,7-5 |
| ITF M15 Hong Kong | 2024/06/12 09:30 | Ajeet Rai v Issei Okamura | 6-1,6-1 |