Kim finished tied for 20th at the
2012 PGA Tour Qualifying School. He was only 17 years, 5 months, 6 days old at the time, the youngest player to graduate from the
PGA Tour's
qualifying school. Due to PGA Tour rules, he could not become a PGA Tour member until he turned 18, midway through the 2013 season. In eight PGA Tour starts in 2013, Kim missed the cut in seven tournaments and withdrew from the eighth. He also played in seven
Web.com Tour events in 2013, making four cuts. Kim played on the Web.com Tour in 2014, making 15 of 19 cuts including a third-place finish at the
Cleveland Open. In 2015, he won his first Web.com Tour event, the
Stonebrae Classic, in July. He was the second-youngest winner in Web.com Tour history, after
Jason Day. He finished 2015 in tenth place in the Web.com Tour money list, to earn a place on the PGA Tour for 2016. His first win on the PGA Tour came at the 2016
Wyndham Championship. At 21, he was the season's youngest winner. His second win on the PGA Tour came at the
2017 Players Championship, beating
Ian Poulter and
Louis Oosthuizen by three-shots with a bogey-free 69 in his final round, becoming the second Korean to win the title after
K. J. Choi in
2011. Ranked 73rd in the world prior to the Players Championship, Kim was the second-lowest ranked player to win the tournament, with 2002 winner
Craig Perks ranked outside 200th before his win. Kim moved up to 28th in the world after the win. Kim lost in a sudden-death playoff at the 2018
RBC Heritage in April. He had held the sole lead for large portions of the final round, but shot three over on the back nine, missing a series of makeable putts, including at the last to win the tournament outright, to fall into a playoff. He lost on the third extra hole of the playoff, when
Satoshi Kodaira holed a lengthy birdie putt on the par-3 17th. In January 2021, Kim won
The American Express in
La Quinta, California. Kim shot a final round 8-under 64 to win by one stroke over
Patrick Cantlay and claim his third PGA Tour title. In August later that year, Kim tied for the lead with five other players after 72 holes at the
Wyndham Championship.
Kevin Kisner took the title in the playoff. In September 2022, Kim was selected for the International team in the
2022 Presidents Cup; he won three and lost one of the four matches he played. In January 2023, Kim won the
Sony Open in Hawaii. He birdied the final two holes to win by one shot over
Hayden Buckley. It was his fourth PGA Tour victory. ==Professional wins (5)==