2023 Slovak Open – Men's singles

Márton Fucsovics was the defending champion but chose not to defend his title.

Gabriel Diallo won the title after defeating Joris De Loore 6–0, 7–5 in the final.

Seeds
• # 🇦🇹 Dominic Thiem (second round)

• # Dominic Stricker (first round)

• # 🇫🇷 Benjamin Bonzi (first round)

• # 🇨🇿 Tomáš Macháč (withdrew)

• # 🇬🇧 Liam Broady (first round)

• # 🇭🇺 Zsombor Piros (second round)

• # 🇺🇸 Maxime Cressy (quarterfinals)

• # 🇸🇰 Alex Molčan (first round)