Martin started her professional boxing career at the age of 21 when she drew in six rounds with Andrea Buchanan in 1989. A rematch one month later had Martin the winner by a two round knockout. One more win followed and then she faced Andrea DeShong, who beat her by a decision in five rounds.19 wins in a row followed, including two wins over Jamie Whitcomb, a win against top rated Suzzane Ricio-Major and a first round knockout in a rubber match with Buchanan. Then, on October 15 of 1993, her first world title shot came, against Beverly Szymansky, for the WBC's version of the women's Jr. Welterweight world championship. Martin became a world champion by knocking out Szymansky in three rounds. In her first defense, she defended her title against debutant Laura Serrano, who held her to a six round draw in Las Vegas.
Martin defended her title six more times, including a rematch with Szymansky, a fourth fight with Buchanan and defenses versus Melinda Robinson and Sue Chase, winning all of them, before the fight that many credit for putting women's boxing on the sports fan's radar took place: On March 16 of 1996, she and Deirdre Gogarty fought what many consider a great fight, in front of Showtime cameras. Martin got the decision, and after that bout, she began to gain more celebrity, even appearing on the cover of Sports Illustrated once shortly afterwards.
Martin kept her winning ways for eight more bouts, beating the likes of Robinson and DeShong once again, Marcela Acuna and Isra Girgrah before her luck ran out and she lost her title on a 10 round decision to Sumya Anani in 1998. After that, she reeled off nine more wins in a row, beating such boxerss as Belinda Laracuente, Sabrina Hall and Kathy Collins.She has also defeated Lisa Holeywine by a decision in ten, and, in her last bout, on December 7 of 2002, she beat Mia St. John, also by a decision in ten.
On June 30, 2003, it was announced she would fight Laila Ali on August 23 of that year. She lost to Ali by knockout in round four.
She currently holds a record of 45 wins, 3 losses and 2 draws with 31 wins by knockout. She is a frequent visitor of the International Boxing Hall Of Fame annual induction ceremonies, and an avid autograph signer. She has fought on the undercards of such boxers as Mike Tyson, Evander Holyfield, Felix Trinidad and Julio Cesar Chavez, to name a few.