1991 Geneva Open – Singles

Horst Skoff was the defending champion, but lost in the final this year.

Thomas Muster won the title, defeating Skoff 6–2, 6–4 in the final.

Seeds
• # 🇪🇸 Sergi Bruguera (quarterfinals)

• # Andrei Cherkasov (first round)

• # Goran Prpić (second round)

• # 🇦🇹 Horst Skoff (final)

• # 🇦🇷 Alberto Mancini (second round)

• # Marc Rosset (first round)

• # 🇦🇷 Guillermo Pérez Roldán (second round)

• # 🇮🇹 Omar Camporese (first round)