Born in McIntyre, Georgia, Brown eventually attended Georgia Tech and had originally planned a career in marine biology before eventually joining the baseball team. In 1986, he was named to the All-America team by The Sporting News. He was renowned for his intensity and his ability, but also his short temper.

In 1986, Brown was drafted by the Texas Rangers in the first round (fourth pick overall). Starting in 1989, Brown was second in the Rangers' rotation behind ace Nolan Ryan and posted a 12-9 record with a 3.35 ERA and 104 strikeouts in 1989 and a 12-10 record with a 3.60 ERA and 88 strikeouts in 1990. By 1992, Brown had improved his record with the Rangers to a remarkable 21-11 with 173 strikeouts and a 3.32 ERA, was tied for the league lead in victories and was the first since Ferguson Jenkins in 1974 to win 20 games in a Ranger uniform.

Brown became a free agent following the strike settlement in 1994 and signed with the Baltimore Orioles for a season, posting a 10-9 record with 117 strikeouts and a 3.60 ERA.

Following the 1995 season, Brown again became a free agent, signing with the Florida Marlins. In his first season with the Marlins, Brown posted a 17-11 record with 159 strikeouts and an MLB best 1.89 ERA, finishing second in the Cy Young Award voting. In 1997, Brown threw a one-hitter game against the Los Angeles Dodgers in his first appearance and a no-hitter against the San Francisco Giants on June 10, 1997, one HBP shy of a perfect game.

In the 1997 National League Championship Series, Brown, riddled with the flu, proceeded to pitch a complete game in Game Six, defeating the Atlanta Braves and helping the Marlins reach the World Series, which they eventually won over the Cleveland Indians.

Following the disassembly of the Marlins' championship team, Brown was traded to the San Diego Padres where he posted an 18-7 record with a career-high 257 strikeouts and a 2.38 ERA, finishing third in the Cy Young Award voting. He helped to lead the Padres to the 1998 World Series, but not before blowing a save in Game 5 of the NLCS during a rare relief appearance.

Following the 1998 season, Brown again became a free agent. He signed a lucrative contract with the Los Angeles Dodgers for 7 years/$105 million USD, becoming the first $100 million man in baseball. Many fans, both in San Diego and nationally, were taken aback by the enormity of the contract given to a player in his mid 30's (almost $40 million more than the Padres offer, the next highest offer he received), and also the choice of team, given Brown expressed a desire to play in a city closer to his Georgia home than San Diego during the season.

His first season in Los Angeles, he posted an 18-9 record with 221 strikeouts and a 3.00 ERA. After leading the NL in ERA during an injury-plagued 2000 season, his performance began to dwindle as Brown was hampered by injuries and poor run support. In 2003, Brown rebounded, producing a respectable 14-9 record with 185 strikeouts and a 2.39 ERA.

On December 11, 2003, Brown was traded to the Yankees as part of a deal that sent Jeff Weaver, Yhency Brazobán, a player to be named later, and $2.6 million in cash to Los Angeles. He went on to a 10-6 record with a 4.09 ERA, but experienced health problems during the season. Toward the end of the season, Brown, leaving Yankee Manager Joe Torre's office in anger, punched the wall outside, breaking his left hand. Brown would be out of action for the remainder of the season. He would pitch in the post season, pitching six innings against Minnesota and only allowing one run in the Division Series. But it was his performance in Game 7 of the 2004 American League Championship Series that he is remembered for, lasting just one inning, giving up 5 runs.

Brown would attempt to come back in 2005, but missed several games during the season due to injury. He would go 4-7 with a 6.50 ERA. On February 20, 2006, Brown announced his retirement. He currently resides in Macon, Georgia.

Salary Kevin Brown was ranked as the 11th highest paid player in baseball at $15,714,286.00.