Korda married Regina Rajchrtová, a former professional tennis player from Czechoslovakia. They have three children, the oldest of whom, Jessica, was born on 27 February 1993; she is a professional golfer, and finished 19th in the 2008 U.S. Women's Open as a 15-year-old, with Korda as her caddy. At the 2013 U.S. Women's Open, Petr caddied for another of their daughters, Nelly, who was 14 years old at the time and the youngest player in the tournament. As of March 2022, Nelly was the #2 ranked woman golfer in the world. His son, Sebastian, is also a tennis player and was the top-ranked junior in the world while representing the United States. Sebastian won the junior boys’ Australian Open title in 2018.