2018 Gimcheon Open ATP Challenger – Singles

Thomas Fabbiano was the defending champion but chose not to defend his title.

Yoshihito Nishioka won the title after defeating Vasek Pospisil 6–4, 7–5 in the final.

Seeds
• # 🇦🇺 Matthew Ebden (first round, retired)

• # 🇨🇦 Vasek Pospisil (final)

• # 🇦🇺 Jordan Thompson (second round)

• # 🇮🇱 Dudi Sela (second round)

• # Lu Yen-hsun (withdrew)

• # 🇺🇸 Mackenzie McDonald (quarterfinals)

• # 🇯🇵 Go Soeda (quarterfinals)

• # Jason Jung (second round)