The 21-year-old South Korean player closed with a 3-under 67 to finish at 21-under 259 at Sedgefield Country Club, tying the tournament 72-hole record set eight years ago by Carl Pettersson.
Kim matched Petterson by sinking an uphill 14-foot birdie putt on the final hole.
Kim set a tournament record with a 60 in the second round. He earned 500 FedEx Cup points and $1,008,000 in prize money in the regular-season finale.
Luke Donald was second at 16 under after a 67. Hideki Matsuyama and Brandt Snedeker were 15 under, also each shooting 67.
