2006 Western & Southern Financial Group Masters – Singles

Andy Roddick defeated Juan Carlos Ferrero in the final, 6–3, 6–4 to win the men's singles tennis title at the 2006 Cincinnati Masters.

Roger Federer was the defending champion, but lost in the second round to Andy Murray. It would be Federer's only defeat prior to a tournament final that season.

Seeds
• # Roger Federer (second round)

• # 🇪🇸 Rafael Nadal (quarterfinals)

• # 🇦🇷 David Nalbandian (second round)

• # Ivan Ljubičić (quarterfinals)

• # 🇷🇺 Nikolay Davydenko (first round)

• # 🇺🇸 James Blake (second round)

• # 🇪🇸 Tommy Robredo (semifinals)

• # 🇨🇾 Marcos Baghdatis (third round)

• # 🇺🇸 Andy Roddick (champion)

• # 🇪🇸 David Ferrer (quarterfinals)

• # 🇨🇿 Tomáš Berdych (first round)

• # 🇫🇮 Jarkko Nieminen (first round)

• # Fernando González (semifinals)

• # 🇩🇪 Tommy Haas (third round)

• # 🇺🇸 Robby Ginepri (third round)

• # 🇸🇰 Dominik Hrbatý (third round)