She admitted she thought about the enormity of a win on Saturday night, but felt calm as she made her way around Sebonack Golf Club course yesterday.
"I didn't feel that much of the pressure when I was on the golf course," said Park, who will go for a fourth consecutive major at the Women's British Open at St. Andrews in August. "I was very nervous yesterday, but on the golf course I felt somehow very calm."
After back-to-back bogeys at the sixth and seventh, Park rebounded with birdies at the ninth and 10th. Despite another brace of bogeys at 14 and 15, she was never seriously threatened.
Kim's 74 left her in second place on 284, and South Korea's Ryu So-Yeon posted an even par 72 for sole possession of third place on 287.
World No1 amateur Lydia Ko has climbed to a share of 36th place after carding 72.
The 16-year-old from the Gulf Harbour Country Club, who had rounds of 72, 76 and 79 to be in a share of 51st place, jumped 15 places but it was not good enough to secure the leading amateur honours for the fifth time in a major.
The world No16 finished on an 11-over-par four round total to be two shots back from American Cassie Cathrea, who came home strong with a two-under-par 70 to claim the low amateur title.
Ko, who had aspirations of becoming the youngest major champion in history, finished 19 shots behind Park.