| Korea Masters 2019, MS, Qualification | 11/07 03:10 | - | Son, Wan Ho v Lee, Dong Keun | D | Retired | |
| Korea Masters 2019, MS, Qualification | 11/07 01:00 | 4 | Choi, Ji Hoon v Lee, Dong Keun | W | 1-2 | |
| Korea Open 2019, MS, Qualification | 07/18 04:00 | - | Son, Wan Ho v Lee, Dong Keun | L | 2-1 | |
| Korea Open 2019, MS, Qualification | 07/18 01:00 | - | Kim, Dong Hoon v Lee, Dong Keun | W | 0-2 | |
| Malaysia Masters 2020, MS, Qualification | 07/05 06:20 | - | Lee, Dong Keun v Tze Yong Ng | L | 0-2 | |
| Malaysia Masters 2020, MS, Qualification | 07/05 02:20 | - | Lee, Dong Keun v Elgamal, Adham Hatem | W | 2-0 | |
| Korea Masters | 04/13 01:20 | 5 | Lee, Dong Keun v Guang Zu Lu | L | 0-2 | |
| Korea Open | 04/06 03:30 | 5 | Jan Louda v Lee, Dong Keun | L | 2-0 | |
| Welsh Int | 12/03 17:40 | - | Verma, Siril v Lee, Dong Keun | L | 2-0 | |
| Welsh Int | 12/03 12:00 | - | Lee, Dong Keun v Varun Kapur | W | 2-1 | |
| Welsh Int | 12/02 13:40 | - | Lee, Dong Keun v Alap Mishra | W | 2-1 | |
| Scottish Open | 11/26 17:40 | - | Arnaud Merkle v Lee, Dong Keun | L | 2-0 | |
| Scottish Open | 11/25 17:30 | - | Kim Bruun v Lee, Dong Keun | W | 1-2 | |
| Hylo Open | 11/04 12:00 | - | Lee, Dong Keun v Srikanth Kidambi | L | 1-2 | |
| Hylo Open | 11/03 15:55 | - | Subhankar Dey v Lee, Dong Keun | W | 0-2 | |
| Open de France | 10/26 12:10 | 5 | Lee, Dong Keun v Sameer Verma | L | 0-2 | |
| Masters d'Espagne | 05/22 12:30 | 2 | Lee, Dong Keun v Toma Junior Popov | L | 0-2 | |
| Masters d'Espagne | 05/21 12:00 | 3 | Lee, Dong Keun v Misha Zilberman | W | 2-0 | |
| Masters d'Espagne | 05/20 12:30 | 4 | Lee, Dong Keun v Pablo Abian | W | 2-0 | |
| Masters d'Espagne | 05/19 10:40 | 5 | Lee, Dong Keun v Ditlev Jaeger Holm | W | 2-0 | |
| India PBL | 02/02 14:30 | - | Priyanshu Rajawat v Lee, Dong Keun | L | 2-0 | |
| India PBL | 01/30 15:10 | - | Lee, Dong Keun v Saensomboonsuk, Tanongsak | L | 0-2 | |
| India PBL | 01/28 14:30 | - | Jayaram, Ajay v Lee, Dong Keun | L | 2-1 | |
| India PBL | 01/25 14:30 | - | Sakai, Kazumasa v Lee, Dong Keun | W | 0-2 | |
| India PBL | 01/22 13:45 | - | Lakshya Sen v Lee, Dong Keun | L | 2-0 | |
| Korea Masters | 11/20 07:00 | 5 | Lee, Dong Keun v Lin, Dan | L | 1-2 | |
| Macau Open 2019, MS | 10/31 05:20 | 4 | Lee, Dong Keun v Thammasin, S. | L | 0-2 | |
| Macau Open 2019, MS | 10/30 02:50 | 5 | June Wei Cheam v Lee, Dong Keun | W | 0-2 | |
| Korea Open 2019, MS, Qualification | 09/24 05:00 | - | Lee, Dong Keun v Kim, Donghun (1993) | L | 0-2 | |
| Korea Open 2019, MS, Qualification | 09/24 01:40 | - | Leverdez, Brice v Lee, Dong Keun | W | 1-2 |