| ITF Women Gyeongsan Qual | 2018/06/10 01:00 | Ji Min Park v Kim, Sung Hee | 2-6,3-6 |
| ITF Women Sangju Qual | 2018/06/05 04:00 | Lee, Jin Ju v Kim, Sung Hee | 2-6,6-4,6-3 |
| ITF Women Sangju Qual | 2018/06/04 05:00 | Kim, Sung Hee v Kamiyoshihara, Ai | 6-3,6-3 |
| ITF Women Sangju Qual | 2018/06/03 03:30 | Oh, Eunji v Kim, Sung Hee | 7-5,5-7,4-6 |
| ITF Women Changwon | 2018/05/23 01:00 | Ozaki, Risa v Kim, Sung Hee | 6-0,6-1 |
| ITF Women Incheon Qual | 2018/05/13 01:00 | Yoo, Jin v Kim, Sung Hee | 6-1,7-5 |
| ITF Women Goyang Qual | 2018/05/07 02:30 | Kim, Sung Hee v Lee, So-Ra | 5-7,2-6 |
| ITF Women Goyang Qual | 2018/05/07 00:30 | Kim, Sung Hee v Kim, Eunseo | 6-0,6-1 |
| ITF Women Sangju Qual | 2018/06/04 05:00 | Kim, Ju-Eun v Kim, Seohyeon | 6-3,7-5 |
| Changwon, Singles Qualifying W-WITF-KOR-01A | 2018/05/20 04:30 | Gilchrist, Nadja v Kim, Seohyeon | 6-2,6-3 |
| ITF Women Yeongwol | 2017/09/03 01:00 | Kim, Da Hye v Kim, Seohyeon | 6-3,6-2 |
| ITF Women Yeongwol | 2016/09/06 01:00 | Chun, Su Yeon v Kim, Seohyeon | 6-1,6-3 |
| ITF Women Yeongwol | 2016/09/05 01:00 | Um, Seon Young v Kim, Seohyeon | 3-6,4-6 |
| ITF Women Yeongwol | 2016/09/04 01:00 | Kim, Seohyeon v Lee, Jeongyun | 6-1,6-0 |
| ITF Women Yeongwol | 2016/08/29 01:00 | Kim, Seohyeon v Kim, SE-Hyun | 4-6,6-1,4-6 |