| Challenger - Noumea | 01/01 04:25 | 25 | [274] Yunseong Chung v Jurij Rodionov [217] | 4-6,1-6 | |
| Challenger - Noumea | 12/31 00:30 | 24 | [262] Yunseong Chung v Tomislav Brkic [309] | 6-3,6-2 | |
| ITF - Katar F5 | 12/11 12:00 | 25 | Yunseong Chung v Kristian Lozan | Cancelled | |
| Australian Open - Wildcard | 11/30 05:45 | 27 | Zhe Li v Yunseong Chung | 6-4,6-4 | |
| Australian Open - Wildcard | 11/29 03:50 | 26 | [402] Rigele Te v Yunseong Chung [266] | 6-7,1-6 | |
| Challenger - Kobe | 11/16 04:45 | 27 | [281] Yunseong Chung v Tatsuma Ito [163] | 2-6,3-6 | |
| Challenger - Kobe | 11/14 05:00 | 26 | [385] Nam Hoang Ly v Yunseong Chung [281] | 4-6,2-6 | |
| Challenger - Kobe | 11/13 02:00 | 25 | [281] Yunseong Chung v Jelle Sels [266] | 7-6,7-6 | |
| Challenger - Liuzhou | 10/23 03:35 | 25 | [149] Miomir Kecmanovic v Yunseong Chung [282] | Retired | |
| Challenger - Liuzhou | 10/22 04:45 | 54 | [282] Yunseong Chung v Emil Ruusuvuori [318] | 6-3,6-3 | |
| Challenger - Liuzhou | 10/21 07:00 | 46 | Yunseong Chung v Youssef Hossam | 7-5,6-3 | |
| Challenger - Liuzhou | 10/20 08:20 | 45 | Yunseong Chung v Sidharth Rawat | 5-7,6-2,6-3 | |
| Challenger - Ningbo | 10/19 03:00 | 27 | [291] Yunseong Chung v Prajnesh Gunneswaran [170] | 2-6,1-6 | |
| Challenger - Ningbo | 10/17 05:15 | 26 | [291] Yunseong Chung v Yosuke Watanuki [220] | 2-6,7-6,6-3 | |
| Challenger - Ningbo | 10/15 04:05 | 25 | [127] Ramkumar Ramanathan v Yunseong Chung [294] | 6-1,6-7,6-7 | |
| Challenger - Tashkent | 10/07 05:00 | 46 | Yunseong Chung v Artem Dubrivnyy | 3-6,5-7 | |
| Challenger - Tashkent | 10/06 05:00 | 45 | Yunseong Chung v Grigoriy Korobeynikov | 6-0,6-0 | |
| Challenger - Kaohsiung | 09/18 10:00 | 25 | [123] Jason Jung v Yunseong Chung [296] | 6-3,6-4 | |
| Challenger - Kaohsiung | 09/17 04:15 | 54 | [293] Yunseong Chung v Tristan Lamasine [345] | 6-4,6-2 | |
| Challenger - Kaohsiung | 09/16 07:45 | 46 | [293] Yunseong Chung v Xin Gao [276] | 7-5,6-3 | |
| Challenger - Kaohsiung | 09/15 12:10 | 45 | [293] Yunseong Chung v N. Vijay Sundar Prashanth [231] | 7-5,6-2 | |
| Challenger - Shanghai | 09/11 07:00 | 25 | [325] Aldin Setkic v Yunseong Chung [293] | 6-3,6-4 | |
| Challenger - Zhangjiagang | 09/07 03:00 | 27 | [315] Yunseong Chung v Alexander Bublik [203] | 4-6,4-6 | |
| Challenger - Zhangjiagang | 09/06 02:00 | 26 | [176] Go Soeda v Yunseong Chung [315] | 5-7,6-3,2-6 | |
| Challenger - Zhangjiagang | 09/05 02:00 | 25 | [315] Yunseong Chung v Roman Safiullin [292] | 3-6,6-4,6-3 | |
| Challenger - Gwangju | 08/14 01:00 | 25 | [312] Yunseong Chung v Benjamin Lock [474] | 4-6,6-4,3-6 | |
| Challenger - Lexington | 08/04 19:50 | 28 | [338] Yunseong Chung v Stefano Napolitano [233] | 5-7,3-6 | |
| Challenger - Lexington | 08/03 23:00 | 27 | [338] Yunseong Chung v Jay Clarke [175] | Retired | |
| Challenger - Lexington | 08/02 14:00 | 26 | Jeffrey John Wolf v Yunseong Chung | 3-6,7-6,5-7 | |
| Challenger - Lexington | 08/01 01:15 | 25 | Yunseong Chung v William Bushamuka | 6-2,6-3 |
Chung Yun-seong (kor.: 정윤성; * 27. März 1998 in Seoul) ist ein südkoreanischer Tennisspieler.