Stadium: Court 3 Round: 46
| Challenger Seoul Qual | 2018/04/28 02:50 | Ji Hoon Son v Seong-Gook Oh | 6-3,6-3 |
| ITF Turkey F5 | 2018/02/08 08:50 | Alessandro Petrone v Ji Hoon Son | 6-2,7-6 |
| ITF Turkey F5 | 2018/02/06 08:30 | Ji Hoon Son v Ji Sung Nam | 4-6,7-6,6-1 |
| ITF Turkey F5 | 2018/02/05 07:30 | Jacopo Berrettini v Ji Hoon Son | 5-7,4-6 |
| ITF Turkey F5 | 2018/02/04 07:30 | Hanyi Liu v Ji Hoon Son | 1-6,0-6 |
| ITF Turkey F4 | 2018/02/02 08:00 | Dragos Dima v Ji Hoon Son | 6-0,6-1 |
| ITF Turkey F4 | 2018/02/01 09:05 | Ji Hoon Son v Cheong-Eui Kim | 6-4,6-4 |
| ITF Turkey F4 | 2018/01/30 07:30 | Duje Kekez v Ji Hoon Son | 1-6,4-6 |
| Challenger Nanchang Qual | 2018/04/15 03:00 | Shuichi Sekiguchi v Yuanfeng Li | 6-3,6-1 |
| Challenger Taipei | 2018/04/11 06:35 | Shuichi Sekiguchi v Dudi Sela | 4-6,2-6 |
| Challenger Taipei Qual | 2018/04/08 07:25 | Toshihide Matsui v Shuichi Sekiguchi | 5-7,6-7 |
| Challenger Taipei Qual | 2018/04/07 08:20 | Vishnu Vardhan v Shuichi Sekiguchi | 4-6,5-7 |
| ITF Japan F4 | 2018/03/27 01:00 | Jacob Grills v Shuichi Sekiguchi | 7-6,4-6,6-3 |
| ITF Japan F3 | 2018/03/22 04:05 | Shuichi Sekiguchi v Sho Katayama | 5-7,6-4,2-6 |
| ITF Japan F3 | 2018/03/19 01:00 | Shuichi Sekiguchi v Jumpei Yamasaki | 6-7,7-6,6-2 |
| ITF Japan F2 | 2018/03/12 02:30 | Seong Chan Hong v Shuichi Sekiguchi | 6-4,1-6,7-6 |