Stadium: Court 2 Round: 25 Ground: Hardcourt outdoor
| Challenger - Busan | 2018/05/15 05:50 | Max Purcell v Na, Jung-Woong | 6-4,6-1 |
| Challenger Gimcheon Qual | 2018/05/05 05:20 | Grills, Jacob v Na, Jung-Woong | 5-7,6-4,6-3 |
| Challenger Seoul Qual | 2018/04/29 02:00 | Na, Jung-Woong v Makoto Ochi | 2-6,4-6 |
| Challenger Seoul Qual | 2018/04/28 03:05 | Na, Jung-Woong v Lee, Tae-Woo | 6-1,6-3 |
| ITF Turkey F5 | 2018/02/08 07:30 | Na, Jung-Woong v Nino Serdarusic | 1-6,2-6 |
| ITF Turkey F5 | 2018/02/06 07:30 | Codescu, Razvan Marius v Na, Jung-Woong | 3-6,0-6 |
| ITF Turkey F5 | 2018/02/05 07:30 | Na, Jung-Woong v Luka Miklavcic | 6-4,6-0 |
| ITF Turkey F5 | 2018/02/04 07:30 | Na, Jung-Woong v Iordache, Sorin Andrei | 6-1,7-6 |
| ITF Vietnam F3 | 2018/05/18 03:00 | Son, Ji Hoon v Nam, Ji Sung | 1-6,2-6 |
| ITF Vietnam F3 | 2018/05/16 03:00 | Son, Ji Hoon v Kushnirovich, Gary | 4-6,7-6,6-1 |
| ITF Vietnam F3 | 2018/05/15 03:00 | Nam Hoang Ly v Son, Ji Hoon | 1-6,4-6 |
| ITF Vietnam F2 | 2018/05/08 03:00 | Nam Hoang Ly v Son, Ji Hoon | 3-6,7-5,6-0 |
| ITF Vietnam F2 | 2018/05/06 04:00 | Son, Ji Hoon v Noh, Sang-Woo | 6-2,6-1 |
| Challenger Seoul | 2018/05/03 08:30 | Jordan Thompson v Son, Ji Hoon | 7-5,7-6 |
| Challenger Seoul Qual | 2018/04/30 03:00 | Wishaya Trongcharoenchaikul v Son, Ji Hoon | 6-7,4-6 |
| Challenger Seoul Qual | 2018/04/29 02:00 | Son, Ji Hoon v Sekiguchi, Shuichi | 6-2,7-6 |