Twenty-eight-year-old Park, who is the Ladies Professional Golf Association's youngest hall of fame qualifier, capped off an exceptional Olympic performance after recovering from injuries that kept her off the course for two months this year.
"I prepared very hard last month to come this week. There was nothing guaranteed because I hadn't played well this season. I had to overcome a lot of obstacles," Park said.
Park was all smiles after receiving the gold medal which she can add to her collection of seven major wins. She shot a 5-under 66 on Saturday, ending the tournament at sixteen under par.
The main suspense on Saturday was who would join Park on the podium.
World number one Lydia Ko of New Zealand birdied the 18th hole to win the silver meal, edging out China's Shanshan Feng by one stroke. The 19-year-old player who had the top seed in the tournament got off to slower start but stormed back in the second-to-last round with a six-under par 65, the best round that day.
"It was a dramatic finish," Ko said.
Park got South Korea's sole medal, which should be some consolation for the country that some said had a chance to sweep the podium, since it sent the biggest squad of all competing nations with four players in the field.
The United States, which had the second most players who qualified with three, missed out on the podium, which U.S. golfer Stacy Lewis said was disappointing.
"I was watching the leader board all day and hoping one of us could get on the podium," Lewis said, who ended tied for fourth and was the highest-placing American.
Thailand's Ariya Jutanugarn, an early leader in the tournament, withdrew on Friday with a knee injury.
Golf returned to the Olympics this year after a more than a 100-year absence. Unlike players in the men's game, all of the top women golfers made the trip to Rio for the tournament.
Silver medallist Ko said the tournament will help to grow the game around the world.
"Before coming here we had some negative press but I think we have all proved what an amazing week it was for golf, for the women's game."
(Editing by Ed Osmond and Nina Chestney)
