2008 U.S. Men's Clay Court Championships – Singles

Ivo Karlović was the defending champion, but chose not to participate that year.

Seventh-seeded Marcel Granollers Pujol won in the final 6–4, 1–6, 7–5, against James Blake.

Seeds
• # 🇺🇸 James Blake (final)

• # 🇩🇪 Tommy Haas (first round)

• # 🇺🇸 Mardy Fish (quarterfinals)

• # 🇺🇸 Sam Querrey (first round)

• # 🇦🇷 Agustín Calleri (quarterfinals)

• # 🇮🇱 Dudi Sela (second round)

• # 🇪🇸 Marcel Granollers Pujol (champion)

• # 🇪🇸 Óscar Hernández (semifinals)