| Davis Cup | 09/12 13:00 | 1 | [52] Dusan Lajovic v Seongchan Hong [194] | 6-4,7-6 | |
| Challenger - Istanbul | 09/04 07:00 | 19 | Seongchan Hong v Yshai Oliel | 4-6,1-6 | |
| Challenger - Istanbul | 09/03 08:35 | 14 | Seongchan Hong v Cengiz Aksu | 6-2,6-4 | |
| US Open | 08/24 14:00 | 15 | [95] Taro Daniel v Seongchan Hong [203] | 6-2,4-6,6-1 | |
| US Open | 08/22 15:00 | 14 | [173] Francesco Passaro v Seongchan Hong [203] | 6-7,4-6 | |
| Challenger - Stanford | 08/14 05:00 | 25 | Alex Michelsen v Seongchan Hong | 4-6,6-2,6-0 | |
| Challenger - Cary | 08/10 21:45 | 26 | [206] Seong Chan Hong v Patrick Kypson [297] | 4-6,4-6 | |
| Challenger - Cary | 08/08 21:45 | 25 | [93] Alexander Shevchenko v Seong Chan Hong [206] | 6-3,3-6,6-7 | |
| Challenger - Lexington | 08/04 17:00 | 27 | [218] Tennys Sandgren v Seong Chan Hong [209] | 6-4,6-2 | |
| Challenger - Lexington | 08/02 17:30 | 26 | [333] Bernard Tomic v Seong Chan Hong [209] | 1-6,2-6 | |
| Challenger - Lexington | 07/31 20:00 | 25 | [320] Nam Hoang Ly v Seong Chan Hong [209] | 1-6,5-7 | |
| Wimbledon | 06/26 10:00 | 14 | [115] Yosuke Watanuki v Seong Chan Hong [197] | 7-6,7-6 | |
| Challenger - Ilkley | 06/17 10:00 | 14 | [160] Dennis Novak v Seong Chan Hong [190] | 6-4,3-6,6-3 | |
| Challenger - Nottingham | 06/13 10:00 | 25 | [190] Seong Chan Hong v Bu Yunchaokete [165] | 6-7,2-6 | |
| Challenger - Surbiton | 06/04 10:00 | 14 | [184] Seong Chan Hong v Jay Clarke [432] | 3-6,3-6 | |
| Challenger - Troisdorf | 05/31 11:00 | 26 | [261] Renzo Olivo v Seong Chan Hong [184] | 6-3,3-6,6-4 | |
| Challenger - Troisdorf | 05/29 15:30 | 25 | [184] Seong Chan Hong v Zsombor Piros [125] | 3-6,6-0,6-0 | |
| French Open | 05/22 08:00 | 14 | [184] Seong-Chen Hong v Matteo Gigante [204] | 5-7,4-6 | |
| Challenger - Busan | 05/09 03:30 | 25 | [319] Jason Jung v Seong Chan Hong [184] | Retired | |
| Challenger - Seoul | 04/28 02:00 | 27 | [194] Seong Chan Hong v Bu Yunchaokete [242] | 4-6,4-6 | |
| Challenger - Seoul | 04/27 02:00 | 26 | [89] Max Purcell v Seong Chan Hong [194] | 1-6,3-6 | |
| Challenger - Seoul | 04/26 04:55 | 25 | Seong Chan Hong v Tatsuma Ito | 6-3,6-2 | |
| Challenger - Tallahassee | 04/22 16:00 | 28 | [156] Zizou Bergs v Seong Chan Hong [200] | 6-2,6-1 | |
| Challenger - Tallahassee | 04/21 15:00 | 27 | [326] Moez Echargui v Seong Chan Hong [200] | 4-6,6-2,1-6 | |
| Challenger - Tallahassee | 04/19 18:15 | 26 | [200] Seong Chan Hong v Rio Noguchi [204] | 6-1,6-4 | |
| Challenger - Tallahassee | 04/17 20:00 | 25 | [472] Christian Harrison v Seong Chan Hong [200] | 3-6,1-6 | |
| Challenger - Sarasota | 04/13 17:05 | 26 | [70] Jason Kubler v Seong Chan Hong [209] | 6-3,6-4 | |
| Challenger - Sarasota | 04/12 18:30 | 25 | [209] Seong Chan Hong v Zachary Svajda [226] | 6-0,6-0 | |
| ATP - Houston | 04/01 21:10 | 14 | [207] Seong Chan Hong v Facundo D Acosta [163] | 2-6,3-6 | |
| Challenger - Mexico City | 03/27 22:45 | 25 | [162] Alejandro Tabilo v Seong Chan Hong [207] | 7-5,6-3 |
Wikipedia - Hong Seong-chan
Hong Seong-chan (kor.: 홍성찬; * 30. Juni 1997 in Gangwon-do) ist ein südkoreanischer Tennisspieler.