Kim, 20, finished at 17-under 271 to edge fellow Korean Pak Se Ri by a shot for her second career LPGA Tour crown.
Pak, a 31-year-old Hall of Famer, birdied seven holes Sunday and shot a 66 for a 272.
Two more Koreans, Han Hee-won (65) and Lee Jee-young (66), tied for third at 15-under 273 with Angela Stanford (67).
Third round co-leader Cristie Kerr (70) was in a large group at 14-under 274.
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