| US Open, New York, USA | 08/19 15:00 | 44 | [168] Sebastian Ofner v Chung, Hyeon [151] | 3-6,3-6 | |
| Vancouver, Canada | 08/16 01:30 | 26 | [195] Maxime Janvier v Chung, Hyeon [135] | 6-4,6-2 | |
| Vancouver, Canada | 08/15 01:30 | 25 | [203] Vasek Pospisil v Chung, Hyeon [135] | 6-1,6-7,3-6 | |
| Challenger Yokkaichi | 08/09 06:05 | 27 | [141] Chung, Hyeon v Sugita, Yuichi [164] | Walkover | |
| Challenger Yokkaichi | 08/08 06:05 | 26 | [141] Chung, Hyeon v Yusuke Takahashi [470] | 3-6,6-1,6-4 | |
| Challenger Yokkaichi | 08/07 03:55 | 25 | Chung, Hyeon v Matthew C Romios | 6-3,6-1 | |
| Chengdu, China | 08/04 03:30 | 29 | [197] Sugita, Yuichi v Chung, Hyeon [166] | 4-6,3-6 | |
| Chengdu, China | 08/03 05:30 | 28 | [154] Tatsuma Ito v Chung, Hyeon [166] | 2-6,6-7 | |
| Chengdu, China | 08/02 04:00 | 27 | [292] Nam, Ji Sung v Chung, Hyeon [166] | 6-7,6-1,3-6 | |
| Chengdu, China | 08/01 03:00 | 26 | [352] Wu, Di v Chung, Hyeon [166] | 6-7,7-6,3-6 | |
| Chengdu, China | 07/30 08:10 | 25 | Takeuchi, Kento (1987) v Chung, Hyeon | 3-6,2-6 | |
| ATP - Barcelone | 04/22 09:00 | 24 | Yoshihito Nishioka v Chung, Hyeon | Cancelled | |
| ATP - Miami | 03/20 15:00 | 23 | Chung, Hyeon v Taro Daniel | Cancelled | |
| ATP - Rotterdam | 02/11 20:05 | 25 | [52] Chung, Hyeon v Nikoloz Basilashvili [20] | 6-4,6-7,2-6 | |
| ATP - Rotterdam | 02/11 10:00 | - | Chung, Hyeon v Bautista-Agut, Roberto | Cancelled | |
| Open d'Australie | 01/17 03:40 | 24 | [25] Chung, Hyeon v Pierre-Hugues Herbert [55] | 2-6,6-1,2-6,4-6 | |
| Open d'Australie | 01/15 01:40 | 23 | [25] Chung, Hyeon v Klahn, Bradley [78] | 6-7,6-7,6-3,6-2,6-4 | |
| ATP - Auckland | 01/08 02:15 | 25 | Rubin Statham v Chung, Hyeon | 7-5,6-3 | |
| ATP Pune | 01/02 09:30 | 26 | [95] Gulbis, Ernests v Chung, Hyeon [25] | 7-6,6-2 | |
| Mubadala World Tennis Championship | 12/28 11:00 | 56 | [25] Chung, Hyeon v Dominic Thiem [8] | 6-2,6-3 | |
| Mubadala World Tennis Championship | 12/27 12:00 | 27 | [25] Chung, Hyeon v Anderson, Kevin [6] | 7-6,2-6,1-6 | |
| ATP Vienna | 10/23 08:00 | 25 | Chung, Hyeon v Isner, John | Cancelled | |
| ATP Stockholm | 10/19 12:00 | 27 | [27] Chung, Hyeon v Fabio Fognini [14] | Retired | |
| ATP Stockholm | 10/17 19:25 | 26 | [27] Chung, Hyeon v Denis Kudla [63] | 6-3,6-3 | |
| ATP Stockholm | 10/16 10:00 | 25 | [27] Chung, Hyeon v Taylor Fritz [56] | 6-2,6-2 | |
| Shanghai, Chine | 10/10 06:50 | 25 | [21] Marco Cecchinato v Chung, Hyeon [26] | 4-6,7-6,7-6 | |
| Shanghai, Chine | 10/09 05:00 | 24 | [93] Hubert Hurkacz v Chung, Hyeon [26] | 4-6,6-2,1-6 | |
| ATP Tokyo | 10/01 04:30 | 25 | [31] Denis Shapovalov v Chung, Hyeon [23] | 6-3,3-6,6-2 | |
| Chengdu, Chine | 09/26 12:05 | 26 | [147] Felix Auger Aliassime v Chung, Hyeon [23] | 7-6,5-7,6-4 | |
| US Open, New York, USA | 08/30 15:00 | 24 | [84] Mikhail Kukushkin v Chung, Hyeon [23] | 7-6,6-2,6-3 |