The 26-year-old South Korean recovered from a bogey on No. 17 with a birdie on the final hole to finish at 11-under 277 and win for the fifth time on the LPGA Tour.
South Korea's Kim Hyo-joo has held off Hinako Shibuno to win the LPGA Lotte Championship by two strokes.
Kim teed off with a three-shot lead on Saturday and was four up after birdies at the fifth and eighth holes at Hoakalei Country Club in Hawaii.
"There have been ups and downs and I think I am at the up part right now and I feel very proud, a little confident about the future and the outlook looks bright for me and I feel like I can do better moving forward," said Kim.
Japan's Shibuno, with birdies at the fourth and 11th, was within one stroke after Kim bogeyed the ninth and 17th.
Kim then missed the fairway at the par-five 18th, her second shot finding the rough.
However, her wedge from the rough rolled within a foot of the cup to leave her a tap-in for birdie that all but sealed the win over Shibuno, who was in a greenside bunker.
Kim signed for a one-under par 71 and an 11-under par total of 277. She notched her fifth LPGA title before she was a member of the LPGA Tour.
Shibuno, the 2019 Women's British Open winner, carded a two-under 70 for 279.
South Korea's Choi Hye-jin was alone in third on 281 after a three-under par 69, with Ashleigh Buhai of South Africa fourth with a 70 for 282.
The win was worth $300,000. Her most recent victory was at the 2021 HSBC Women's World Championship in Singapore.
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Never a doubt 🏆— LPGA (@LPGA) April 17, 2022
Hyo Joo Kim wins the @LPGALOTTE by two 👏
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