2009 Rakuten Japan Open Tennis Championships – Singles

Tomáš Berdych was the defending champion, but he lost in the quarterfinals to Mikhail Youzhny.

Second-seeded Jo-Wilfried Tsonga won in the final 6–3, 6–3 against Mikhail Youzhny.

Seeds
• # 🇦🇷 Juan Martín del Potro (first round)

• # 🇫🇷 Jo-Wilfried Tsonga (champion)

• # 🇫🇷 Gilles Simon (second round)

• # 🇫🇷 Gaël Monfils (semifinals)

• # 🇨🇿 Tomáš Berdych (quarterfinals)

• # 🇨🇿 Radek Štěpánek (first round)

• # Stanislas Wawrinka (quarterfinals)

• # 🇦🇺 Lleyton Hewitt (semifinals)

Seeds
• # Ernests Gulbis (qualified)

• # Marco Chiudinelli (qualified)

• # 🇮🇳 Somdev Devvarman (first round)

• # 🇫🇷 Édouard Roger-Vasselin (qualified)

• # 🇰🇷 Im Kyu-tae (qualifying competition)

• # 🇹🇷 Marsel İlhan (qualified)

• # 🇩🇪 Dominik Meffert (qualifying competition)

• # Rik de Voest (qualifying competition)

Qualifiers
• # Ernests Gulbis

• # Marco Chiudinelli

• # 🇹🇷 Marsel İlhan

• # 🇫🇷 Édouard Roger-Vasselin