Mayfield began racing in his hometown of Owensboro, BMX bike racing. He then proceeded to race go-karts at local short tracks, moving to Nashville Speedway USA at the age of 19 years. He soon went to work for Sadler Bros. Racing as a manufacturer, and became his driver, winning Rookie of the Year Late Model Motor Speedway Kentucky in 1987.
In 1993, he joined the ARCA series, and was named Rookie of the Year. He also made his Cup debut at the Mello Yello 500, from 30 and finishing 29th in the # 95 Ford Thunderbird sponsored by Mac Tools.
In 1994, Mayfield said that he would run for NASCAR Winston Cup Series Rookie of the Year, and Sadler signed to drive the # 95 Ford Bros. Shoney. He fought a lot in 95, and was released. He signed to drive the # 02 of TWTaylor, sponsored by the Miracle Network children in four runs, before ending the year at Ford # 98 Cale Yarborough Fingerhut. He ran 20 races in his first season, his best result in a 19 in Rockingham. In 1995, Yarborough was left with full-time with the new sponsorship of the RCA, and had an eighth-place run in the Miller Genuine Draft 500 with a 31st place finish in the standings after 27 out of 31 rating careers. The next season, had two top five and won his first pole in the DieHard 500. Later that season, was released and replaced John Andretti # 37 in the Kmart / Little Caesars Ford is owned by Michael Kranefuss. Mayfield finished the year 26 in the points.
In 2002, Mayfield signed with Evernham Motorsports to replace Casey Atwood. In its first year, Mayfield was about forty high and finished 26 th in points. He recovered some in 2003, winning the pole in the Aaron's 499 and posting 12 top ten, finishing nineteenth in the championship. Finally, in 2004, Mayfield returned to victory in the Chevy Rock and Roll 400 earning his ninth team in the inaugural Chase for the Cup, and finished tenth in the championship. For a time, winning a race to the Chase was sent by the nickname of "pulling a Jeremy Mayfield." In 2005, he won the GFS Marketplace 400, and finished ninth in the standings. In August 2006 he was released from Evernham after his team fell from the top-35 in owner points, and replaced by Bill Elliott and Elliott Sadler.
Mayfield signed with Bill Davis Racing for 2007, driving the # 36 Toyota Camry with the sponsorship of 360 OTC. Associate sponsors include the World Wrestling Entertainment, the television network TNT, and rock band KISS. He ran a total of 13 Bill Davis Racing races in 32 attempts with a best finish of 22 at Kansas Speedway. In August 2007, Mayfield and Davis announced that forms at the end of the season. Later in the season, which would take over driving the car # 66 Best Buy Haas CNC Racing from Atlanta 2007. In late 2007, he and his teammate Scott Riggs change Mayfield walks end in the # 70 of the 2008 season.
Mayfield completed seven races in the # 70 with a best finish of the sixteenth before being released from the team. I was going to complete an additional race at Dover in the No. 40 Target Dodge, replacing the injured Dario Franchitti. It started tenth and finished 25th.
In January 2009, Mayfield announced that the intent of the entire season in a car owned by Toyota, with the number 41. He ran his way into the Daytona 500. After 10 races in the 2009 season, Mayfield qualified for only 5. After their dispute have substance abuse later in most aspects of his racing career ended and as of July 16, 2009 Mayfield sold his race team and operations due to lack of sponsorship and the last member of his team after giving up all other members of the race team were fired.
On May 9, 2009, Mayfield was suspended indefinitely by NASCAR for violating NASCAR's policy of substance abuse.