The South Korean carded an eight-under 64 in the final round at the PGA West Stadium Course to finish at 23 under.
It was enough for Kim to win his first PGA Tour crown since May 2017 and third overall.
Kim’s win came despite a spectacular final round from Patrick Cantlay, who fired a stunning 11-under 61.
Cantlay broke the course record on the back of 11 birdies.
Australian Cameron Davis finished outright third after a fine eight-under 64 in the final round.
Tony Finau and Max Homa were tied for the overnight lead with Kim, but they slipped back to finish fourth and tied for 21st respectively.
Abraham Ancer (66), Michael Thompson (66) and Doug Ghim (69) finished at 15 under.
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