Round: 26 Ground: Hardcourt outdoor
| ITF Japan F4 | 2018/03/27 03:00 | Takeuchi, Kento (1987) v Katayama, Sho | 6-4,4-6,5-7 |
| ITF Japan F3 | 2018/03/22 08:45 | Katayama, Sho v Kaito Uesugi | 3-6,1-6 |
| ITF Japan F3 | 2018/03/22 04:05 | Sekiguchi, Shuichi v Katayama, Sho | 5-7,6-4,2-6 |
| ITF Japan F3 | 2018/03/19 01:00 | Katayama, Sho v Moritani, Soichiro | 6-2,6-0 |
| ITF Japan F2 | 2018/03/13 03:00 | Kaichi Uchida v Katayama, Sho | 7-6,6-3 |
| ITF Japan F1 | 2018/03/08 01:30 | Katayama, Sho v Yuta Shimizu | 4-6,1-6 |
| ITF Japan F1 | 2018/03/06 02:00 | Shintaro Imai v Katayama, Sho | 2-6,5-7 |
| Yokohama, Japan, Qualifying | 2018/02/25 02:20 | Hiroki Moriya v Katayama, Sho | 6-3,6-0 |
| ITF Japan F4 | 2018/03/28 01:00 | Kibi, Yuya v Tamaki Yamao | 6-0,4-6,2-6 |
| ITF Japan F4 | 2018/03/25 01:00 | Tamaki Yamao v Ko Suzuki | 6-4,6-2 |
| ITF Japan F4 | 2018/03/24 00:00 | Lee, Tae-Woo v Tamaki Yamao | 1-6,4-6 |
| ITF Japan F3 | 2018/03/19 01:00 | Tamaki Yamao v Ehara, Hiroyasu | 6-2,3-6,0-6 |
| ITF Japan F3 | 2018/03/18 01:00 | Uesugi, Teppei v Tamaki Yamao | 3-6,4-6 |
| ITF Japan F3 | 2018/03/17 02:30 | Tamaki Yamao v Murray, Jack | 4-6,6-3,6-2 |
| ITF Japan F3 | 2018/03/17 00:30 | Tamaki Yamao v Taketo Takamisawa | 6-1,6-3 |
| ITF Japan F2 | 2018/03/13 04:40 | Tamaki Yamao v Makoto Ochi | 7-5,3-6,1-6 |