1991 Volvo San Marino Open

The 1991 Volvo San Marino Open was a women's tennis tournament played on outdoor clay courts at the Centro Sportivo Tennis in the City of San Marino, San Marino that was part of the Tier V category of the 1991 WTA Tour. It was the inaugural edition of the WTA San Marino and was held from 15 July until 21 July 1991. Second-seeded Katia Piccolini won the singles title and earned $13,500 first-prize money.

Singles
🇮🇹 Katia Piccolini defeated 🇮🇹 Silvia Farina 6–2, 6–3
 * It was Piccolini's only singles title of her career.

Doubles
🇦🇺 Kerry-Anne Guse / 🇯🇵 Akemi Nishiya defeated 🇮🇹 Laura Garrone / 🇦🇷 Mercedes Paz 6–0, 6–3