The 34-year-old star, who is currently at No.2 in the US Billboard chart with viral hit 'Gangnam Style', thrilled fans with his signature galloping dance move dubbed 'Seoul Style' before taking his top off.
Addressing the crowd in front of Seoul City Hall, the singer and songwriter said: "I did not get here because I was worthy of it. I'm here because of all of you. I'm just a fat man with two kids.
"It's a golden opportunity to show the world how well we Koreans play."
Psy's music video for 'Gangnam Style' has been viewed over 350 million times on YouTube and is currently at the top of the UK chart.
See pictures of Psy performing in Seoul here:
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