He was 1.63 seconds faster than the silver medalist Nikita Tregubov of the Olympic Athletes from Russian Federation.
Yun, now No. 1 in the International Bobsleigh and Skeleton Federation (IBSF) rankings, claimed gold in the men's skeleton competition at the 23rd Winter Olympics on Friday, with a combined time of 3 minutes, 20.55 seconds after four runs.
Since South Korea first appeared at the Winter Olympic Games in 1948, all 55 of its medals, including the medals won at the PyeongChang Winter Olympics, had come from skating sports, with 43 of them earned by short trackers.
The host country was center stage in Pyeongchang on Thursday night, with Yun Sung-bin of South Korea winning the gold medal to highlight Day 7 of the 2018 Winter Olympics.
Yun's time: 1 minute, 40.35 seconds. This is the first time that any athlete outside of Europe or North America has won an Olympic medal in the sliding event.
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The United States team added three more medals on Sunday, with a silver medal won by Chris Mazdzer in the luge and a bronze medal won by the Americans in the team figure skating competition.
Yun, who made history last month by becoming the first Korean world champion in men's skeleton, did not take part in the final round of the season in Germany in order to practise for the Olympics. She repeated as the gold medal victor after also taking first place in Sochi. The fourth heat is scheduled to start at 11:15 a.m. Yun later told reporters that he appreciated his fans. Getting us started the right way!
Head coach Lee Yong said Yun knew the curves and turns of the Olympic Sliding Centre better than anyone.
"It feels unbelievable to win Olympic gold", said Yun.
He was the most consistent performer throughout the competition as he headed into his fourth and final run with an incredible lead of more than a second.