# 2023 Busan Open – Singles

Kamil Majchrzak was the defending champion but chose not to defend his title.
Aleksandar Vukic won the title after Max Purcell retired trailing 4–6, 0–1 in the final.

## Seeds

* Max Purcell (final, retired)
* Christopher Eubanks (quarterfinals)
* Jordan Thompson (quarterfinals)
* Emilio Gómez (first round)
* Rinky Hijikata (second round)
* Aleksandar Vukic (champion)
* Kaichi Uchida (first round)
* Gabriel Diallo (semifinals)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| 1 | Max Purcell | 6 | 7 | | | | |
| 8 | Gabriel Diallo | 4 | 5 | | | | |
| 8 | Gabriel Diallo | 4 | 5 | 1 | Max Purcell | 4 | 0$^r$ |
| | | | | 6 | Aleksandar Vukic | 6 | 1 |
| | Brandon Holt | 6$^4$ | 1 | 6 | Aleksandar Vukic | 6 | 1 |
| 6 | Aleksandar Vukic | 7$^7$ | 6 | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | M Purcell | 6 | 6 | | | | | | | | | | | | | | |
| Q | Yuki Mochizuki | 3 | 3 | | 1 | M Purcell | 6 | 6 | | | | | | | | | |
| Q | Renta Tokuda | 6$^4$ | 3 | | | Y-h Hsu | 2 | 4 | | | | | | | | | |
| | Y-h Hsu | 7$^7$ | 6 | | | | | | | 1 | M Purcell | 6 | 7 | | | | |
| WC | H Chung | 3 | 7$^7$ | 2 | | | | | | Q | Y Uchiyama | 4 | 5 | | | | |
| Q | Y Uchiyama | 6 | 6$^3$ | 6 | Q | Y Uchiyama | 6 | 3 | 6 | | | | | | | | |
| Alt | O Jasika | 7$^8$ | 3 | 2 | 5 | R Hijikata | 4 | 6 | 4 | | | | | | | | |
| 5 | R Hijikata | 6$^6$ | 6 | 6 | | | | | | | | | | 1 | M Purcell | 6 | 7 |
| 3 | J Thompson | 6 | 6 | | | | | | | | | | | 8 | G Diallo | 4 | 5 |
| Alt | D Masur | 1 | 1 | | 3 | J Thompson | 7 | 6 | | | | | | | | | |
| | E Donskoy | 7 | 3 | 6 | | E Donskoy | 5 | 3 | | | | | | | | | |
| | Y Shimizu | 5 | 6 | 0 | | | | | | 3 | J Thompson | 3 | 5 | | | | |
| WC | Y-s Chung | 7 | 6 | | | | | | | 8 | G Diallo | 6 | 7 | | | | |
| | T-l Wu | 5 | 2 | | WC | Y-s Chung | 6$^5$ | 6$^4$ | | | | | | | | | |
| WC | J-s Nam | 3 | 3 | | 8 | G Diallo | 7$^7$ | 7$^7$ | | | | | | | | | |
| 8 | G Diallo | 6 | 6 | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 7 | K Uchida | 2 | 4 | | | | | | | | | | | | | | |
| | A Çelikbilek | 6 | 6 | | | A Çelikbilek | 4 | 6$^5$ | | | | | | | | | |
| | Y Bu | 4 | 4 | | | L Tu | 6 | 7$^7$ | | | | | | | | | |
| | L Tu | 6 | 6 | | | | | | | L Tu | 4 | 4 | | | | | |
| | R Berankis | 6$^3$ | 3 | | | | | | | B Holt | 6 | 6 | | | | | |
| Q | L Saville | 7$^7$ | 6 | | Q | L Saville | 3 | 3 | | | | | | | | | |
| | B Holt | 6 | 6 | | | B Holt | 6 | 6 | | | | | | | | | |
| 4 | E Gómez | 2 | 2 | | | | | | | | | | | | B Holt | 6$^4$ | 1 |
| 6 | A Vukic | 7$^7$ | 6 | | | | | | | | | | | 6 | A Vukic | 7$^7$ | 6 |
| | L Harris | 6$^5$ | 3 | | 6 | A Vukic | 7$^7$ | 6 | | | | | | | | | |
| | S Shimabukuro | 6$^2$ | 6 | 7 | | S Shimabukuro | 6$^1$ | 4 | | | | | | | | | |
| Q | H Moriya | 7$^7$ | 2 | 5 | | | | | 6 | A Vukic | 6$^4$ | 7$^7$ | 6 | | | | |
| Q | J Jung | 6 | 3 | | | | | | 2 | C Eubanks | 7$^7$ | 6$^3$ | 4 | | | | |
| | S-c Hong | 2 | 0$^r$ | | Q | J Jung | 4 | 3 | | | | | | | | | |
| | M Polmans | 6 | 3 | 6$^6$ | 2 | C Eubanks | 6 | 6 | | | | | | | | | |
| 2 | C Eubanks | 4 | 6 | 7$^8$ | | | | | | | | | | | | | |