2012 Citi Open – Men's singles

Radek Štěpánek was the defending champion, but opted to play at the London Summer Olympics instead. Alexandr Dolgopolov defeated Tommy Haas in three sets for the title, 6–7(7–9), 6–4, 6–1.

Seeds
• # 🇺🇸 Mardy Fish (semifinals)

• # 🇺🇦 Alexandr Dolgopolov (champion)

• # Kevin Anderson (quarterfinals)

• # 🇩🇪 Tommy Haas (final)

• # 🇪🇸 Pablo Andújar (first round)

• # 🇫🇷 Jérémy Chardy (second round)

• # 🇫🇷 Benoît Paire (first round)

• # 🇺🇸 Sam Querrey (semifinals)

Seeds
• # 🇺🇸 Michael Russell (qualified)

• # 🇺🇸 Jesse Levine (qualified)

• # 🇩🇪 Michael Berrer (qualifying competition)

• # 🇫🇷 Florent Serra (qualified)

• # Paul Capdeville (first round)

• # Marco Chiudinelli (qualified)

• # 🇺🇸 Wayne Odesnik (first round, retired because of exhaustion)

• # 🇷🇺 Teymuraz Gabashvili (qualifying competition)

Qualifiers
• # 🇺🇸 Michael Russell

• # 🇺🇸 Jesse Levine

• # Marco Chiudinelli

• # 🇫🇷 Florent Serra