2005 Porsche Tennis Grand Prix – Singles

Defending champion Lindsay Davenport defeated Amélie Mauresmo in a rematch of the previous year's final, 6–2, 6–4 to win the singles tennis title at the 2005 Stuttgart Open.

Seeds
The first four seeds received a bye into the second round. • # 🇺🇸 Lindsay Davenport (champion)

• # 🇧🇪 Kim Clijsters (quarterfinals)

• # 🇫🇷 Amélie Mauresmo (final)

• # 🇧🇪 Justine Henin-Hardenne (second round)

• # 🇷🇺 Elena Dementieva (semifinals)

• # 🇷🇺 Nadia Petrova (quarterfinals)

• # Patty Schnyder (second round)

• # 🇷🇺 Anastasia Myskina (quarterfinals)