1991 Donnay Indoor Championships – Singles

Boris Becker was the defending champion, but retired from his semifinals match this year.

Guy Forget won the title, defeating Andrei Cherkasov 6–3, 7–5, 3–6, 7–6 in the final.

Seeds
• # Boris Becker (semifinals, retired)

• # 🇸🇪 Stefan Edberg (semifinals)

• # 🇺🇸 Andre Agassi (first round)

• # 🇫🇷 Guy Forget (champion)

• # 🇸🇪 Jonas Svensson (first round)

• # Andrei Chesnokov (quarterfinals)

• # 🇺🇸 Michael Chang (quarterfinals)

• # Jakob Hlasek (quarterfinals)