The 2009 San Marino CEPU Open was a professional tennis tournament played on outdoor red clay courts. It was the twenty-first edition of the tournament which was part of the Tretorn SERIE+ of the 2009 ATP Challenger Tour. It took place in City of San Marino, San Marino between 3 and 9 August 2009.

Singles entrants

Seeds

Other entrants

The following players received wildcards into the singles main draw: The following players received a Special Exempt into the main draw: The following players received entry from the qualifying draw:

Champions

Singles

🇮🇹 Andreas Seppi def. 🇮🇹 Potito Starace, 7–6(4), 2–6, 6–4

Doubles

🇦🇷 Lucas Arnold Ker / 🇦🇷 Sebastián Prieto def. 🇸🇪 Johan Brunström / Jean-Julien Rojer, 7–6(4), 2–6, [10–7]