Petty is a second generation driver. His father, Lee Petty, won the first Daytona 500 in 1959 and was also a three-time NASCAR champion. His son Kyle is also a well-known NASCAR driver. His grandson, Adam (Kyle's son), was killed in a practice crash at New Hampshire International Speedway on May 12, 2000, five weeks after Lee's death. Adam's brother Austin works on day-to-day operations of the Victory Junction Gang Camp, a Hole in the Wall Gang Camp established by the Pettys after Adam's death. Petty married Lynda Owens in 1958. She died on March 25, 2014 at her home in Level Cross, North Carolina at age 72, after a long battle with cancer. They had four children—Kyle Petty, Sharon Petty-Farlow, Lisa Petty-Luck, and Rebecca Petty-Moffit. The family resides in Petty's home town of Level Cross, North Carolina and operates Richard Petty Motorsports. The Richard Petty Museum was formerly in nearby Randleman, North Carolina but moved back to its original location in March 2014
He performed the voice of The King in Cars. He was married to Lynda Petty (who died on March 25, 2014 at her home in Level Cross, North Carolina after a long battle with cancer, at age 72), who had performed the voice of The King's wife Lynda Weathers.