During her career, she has won three Grand Slam singles titles (2 Australian Open, 1 French Open), as well as the women's singles Gold Medal at the 1992 Olympic Games.

Capriati was introduced to tennis while she was still a toddler by her father, Stefano Capriati, an Italian-American former boxer turned tennis coach, who has continued to coach her in her later professional career.

In 1986, when Jennifer's burgeoning tennis talent became obvious, her family moved to Florida, where the ten-year-old player was enrolled in an intense training program run by Jimmy Evert, the father of Chris Evert.

In 1989, Capriati served notice to the tennis world by becoming the youngest player to win the French Open junior singles title at the age of 13 years and 2 months. (The record stood until 1993, when it was broken by Martina Hingis who won the title as a 12-year-old). Capriati went on to win the junior singles title at the 1989 US Open, and the junior doubles titles at both the US Open and Wimbledon (partnering Meredith McGrath).

Capriati turned professional on March 5 1990, three weeks before her 14th birthday. In her debut tournament on the tour, at Boca Raton, Florida, she defeated four seeded players on her way to becoming the youngest-ever player to reach a tour final, where she lost 6-4, 7-5 to Gabriela Sabatini.

Three months later, she became the youngest-ever semi-finalist at the French Open (aged 14 years and 2 months), where she lost to the eventual champion Monica Seles. Capriati went on to reach the fourth round at both Wimbledon and the US Open that year, and won her first top-level singles title that October at San Juan, Puerto Rico. She finished her first year on the tour ranked the World No. 8.

1991 saw Capriati reach the semi-finals at Wimbledon and the US Open. She became Wimbledon's youngest-ever semi-finalist after defeating the defending-champion Martina Navratilova in the quarter-finals, forcing Navratilova's earliest Wimbledon exit for 14 years. She won two singles titles that year, as well as her first (and only) tour doubles title (in Rome partnering Monica Seles).

The biggest moment of Capriati's early-career came in 1992, when she won the women's singles Gold Medal at the Olympic Games in Barcelona. In the final, she defeated Steffi Graf (who was the Gold Medalist four years earlier in Seoul) in three sets 3-6, 6-3, 6-4.