Stadium: Center Court Round: 25 Ground: Hardcourt outdoor
| Challenger Kobe | 2017/11/07 04:25 | Duckhee Lee v Tatsuma Ito | 2-6,1-6 |
| Challenger Gimcheon | 2017/05/02 05:55 | Tatsuma Ito v Duckhee Lee | 6-4,3-6,4-6 |
| Challenger - Shenzhen | 2017/03/14 06:00 | Duckhee Lee v Tatsuma Ito | 6-1,5-7,6-4 |
| Challenger Kaohsiung | 2015/09/21 07:40 | Tatsuma Ito v Duckhee Lee | 4-6,7-6,6-3 |
| Nanchang, China | 2018/04/17 03:00 | Yunseong Chung v Tatsuma Ito | 6-4,7-6 |
| Challenger - Taipei | 2018/04/14 06:55 | Tatsuma Ito v Bhambri, Yuki | 6-3,3-6,4-6 |
| Challenger - Taipei | 2018/04/13 07:30 | Jason Jung v Tatsuma Ito | 6-3,6-7,6-7 |
| Challenger - Taipei | 2018/04/12 13:15 | Soonwoo Kwon v Tatsuma Ito | 6-4,6-7,4-6 |
| Challenger - Taipei | 2018/04/11 03:00 | Grigelis, Laurynas v Tatsuma Ito | 7-6,4-6,3-6 |
| ITF Japan F3 | 2018/03/23 02:00 | Tatsuma Ito v Hong, Seong Chan | 5-7,6-2,2-6 |
| ITF Japan F3 | 2018/03/22 06:55 | Tatsuma Ito v Ryota Tanuma | 6-7,6-2,6-1 |
| ITF Japan F3 | 2018/03/22 03:00 | Tatsuma Ito v Masamichi Imamura | 6-2,6-0 |
| Anning, China | 2018/04/26 04:35 | Mukund Sasikumar v Duckhee Lee | 6-2,7-6 |
| Anning, China | 2018/04/24 06:20 | Duckhee Lee v Wang, Ruixuan | 6-2,7-6 |
| Nanchang, China | 2018/04/16 03:00 | Duckhee Lee v Jordan Thompson | 2-6,1-6 |
| ITF Japan F5 | 2018/04/03 05:35 | Duckhee Lee v Kawahashi, Yuta | 6-7,6-7 |
| Challenger Qujing | 2018/03/20 02:00 | Duckhee Lee v Hubert Hurkacz | 3-6,3-6 |
| Challenger - Shenzhen | 2018/03/15 09:20 | Jaziri, Malek v Duckhee Lee | 6-2,6-2 |
| Challenger - Shenzhen | 2018/03/13 05:55 | Jason Jung v Duckhee Lee | 6-4,5-7,4-6 |
| Challenger Yokohama | 2018/02/28 01:30 | Duckhee Lee v Cem Ilkel | 2-6,6-2,6-7 |