2010 Rakuten Japan Open Tennis Championships – Singles

Jo-Wilfried Tsonga was the defending champion, but was eliminated in the first round by Jarkko Nieminen.

Top seed Rafael Nadal defeated Gaël Monfils 6–1, 7–5 to become the event's third Spanish winner since David Ferrer won in 2007.

Seeds
• # 🇪🇸 Rafael Nadal (champion)

• # 🇺🇸 Andy Roddick (quarterfinals)

• # 🇫🇷 Jo-Wilfried Tsonga (first round)

• # 🇦🇹 Jürgen Melzer (second round)

• # 🇫🇷 Gaël Monfils (final)

• # 🇪🇸 Feliciano López (second round)

• # Ernests Gulbis (first round)

• # 🇫🇷 Michaël Llodra (first round)

Seeds
• # 🇧🇷 Ricardo Mello (first round)

• # 🇹🇷 Marsel İlhan (qualifying competition)

• # 🇫🇷 Édouard Roger-Vasselin (qualified)

• # 🇩🇪 Mischa Zverev (first round)

• # Ivan Dodig (qualified)

• # 🇧🇷 Thiago Alves (first round)

• # 🇱🇺 Gilles Müller (first round)

• # 🇺🇸 Rajeev Ram (qualified)

Qualifiers
• # 🇺🇸 Rajeev Ram

• # 🇨🇦 Milos Raonic

• # 🇫🇷 Édouard Roger-Vasselin

• # Ivan Dodig