1991 Athens Open – Singles

Mark Koevermans was the defending champion, but lost in the quarterfinals this year.

Sergi Bruguera won the tournament, beating Jordi Arrese in the final, 7–5, 6–3.

Seeds
• # 🇪🇸 Sergi Bruguera (champion)

• # Goran Prpić (first round)

• # 🇪🇸 Javier Sánchez (second round)

• # 🇦🇹 Thomas Muster (semifinals)

• # 🇪🇸 Francisco Clavet (semifinals)

• # 🇦🇷 Guillermo Pérez Roldán (quarterfinals)

• # 🇦🇷 Martín Jaite (first round)

• # 🇪🇸 Jordi Arrese (final)