The 2018 Gwangju Open was a professional tennis tournament played on hard courts. It was the 3rd edition of the tournament which was part of the 2018 ATP Challenger Tour. It took place in Gwangju, South Korea between 13 and 19 August 2018.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Spain | Marcel Granollers | 108 | 1 | |
| Henri Laaksonen | 124 | 2 | ||
 Kazakhstan | Alexander Bublik | 172 | 3 | |
 Korea, Republic of | Lee Duck-hee | 239 | 4 | |
 Australia | Akira Santillan | 282 | 5 | |
| Australia | Maverick Banes | 284 | 6 | |
| Ulises Blanch | 301 | 7 | ||
 Japan | Renta Tokuda | 307 | 8 |
The following players received wildcards into the singles main draw:
Chung Hong Jeong Yeong-seok Kim Cheong-eui Sin Dong-hakThe following player received entry into the singles main draw as an alternate:
The following player received entry into the singles main draw as a special exempt:
Xia ZihaoThe following players received entry from the qualifying draw:
He Yecong Nam Ji-sung
Sidharth Rawat Son Ji-hoonSee main article: 2018 Gwangju Open – Singles.
Maverick Banes def. Nam Ji-sung 6–3, 4–6, 6–4.See main article: 2018 Gwangju Open – Doubles.
Nam Ji-sung / Song Min-kyu def. Benjamin Lock / 
Rubin Statham 5–7, 6–3, [10–5].