2023 Nonthaburi Challenger II – Singles

Dennis Novak was the defending champion but lost in the semifinals to Arthur Cazaux.

Cazaux won the title after defeating Lloyd Harris 7–6(7–5), 6–2 in the final.

Seeds
• # 🇦🇹 Dennis Novak (semifinals)

• # Lloyd Harris (final)

• # 🇵🇱 Kacper Żuk (first round)

• # 🇨🇿 Zdeněk Kolář (first round)

• # 🇧🇪 Michael Geerts (second round)

• # 🇵🇱 Daniel Michalski (quarterfinals)

• # 🇯🇵 Sho Shimabukuro (first round)

• # 🇺🇸 Tennys Sandgren (quarterfinals)