The 1991 Mazda Classic was a women's tennis tournament played on outdoor hard courts at the La Costa Resort and Spa in San Diego, California in the United States that was part of Tier III of the 1991 WTA Tour. It was the 13th edition of the tournament and was held from July 29 through August 5, 1991. Fourth-seeded Jennifer Capriati won the singles title and earned $45,000 first-prize money.
It was the tournament's first year in La Costa after moving from the San Diego Tennis & Racquet Club. It was also Mazda's first year as sponsor after replacing Great American Bank, a San Diego-based institution that was in financial decline.[1]
See main article: 1991 Mazda Classic – Singles. 
Jennifer Capriati defeated Monica Seles, 4–6, 6–1, 7–6(7–2)
See main article: 1991 Mazda Classic – Doubles. 
Jill Hetherington / Kathy Rinaldi defeated Gigi Fernández / 
Nathalie Tauziat, 6–4, 3–6, 6–2