2005 Allianz Suisse Open Gstaad – Singles

Roger Federer was the defending champion, but did not participate this year.

Gastón Gaudio won the tournament, beating Stanislas Wawrinka in the final, 6–4, 6–4.

Seeds
• # 🇷🇺 Nikolay Davydenko (first round, retired due to a wrist injury)

• # 🇦🇷 Gastón Gaudio (champion)

• # 🇨🇿 Radek Štěpánek (second round)

• # 🇪🇸 David Ferrer (first round)

• # Ivan Ljubičić (second round)

• # 🇨🇿 Jiří Novák (first round)

• # Nicolás Massú (semifinals)

• # 🇮🇹 Filippo Volandri (first round)