Round: 25 Ground: Hardcourt outdoor
| Challenger Shymkent Qual | 2017/05/22 05:00 | Daniel Nguyen v Evgeny Karlovskiy | 4-6,0-6 |
| Challenger Shymkent Qual | 2017/05/21 05:00 | Daniel Nguyen v Denis Matsukevich | 7-5,6-0 |
| Challenger Busan Qual | 2017/05/15 03:35 | Austin Krajicek v Daniel Nguyen | 6-1,6-3 |
| Challenger Busan Qual | 2017/05/14 05:45 | Ji Hoon Son v Daniel Nguyen | 1-6,5-7 |
| Challenger Busan Qual | 2017/05/13 05:10 | Daniel Nguyen v Felix Auger Aliassime | 7-5,6-1 |
| Challenger Seoul | 2017/05/10 01:30 | Alexander Sarkissian v Daniel Nguyen | 6-3,6-4 |
| Challenger Seoul Qual | 2017/05/08 02:00 | Matthew Ebden v Daniel Nguyen | 2-6,0-6 |
| Challenger Seoul Qual | 2017/05/07 01:30 | Raymond Sarmiento v Daniel Nguyen | 6-3,6-7,2-6 |
| ITF Korea F1 Qual | 2017/05/29 01:00 | Jaeyoung Park v Geon Ju Shin | 6-3,6-4 |
| ITF Korea F1 Qual | 2017/05/28 01:00 | Jae-Min Seol v Jaeyoung Park | 6-2,4-6,4-6 |
| ITF Korea F1 Qual | 2017/05/27 01:00 | Jaeyoung Park v Ki Su Jung | 7-5,6-3 |