It was not until he enrolled at Dong-Eui University, known for its fencing team, that he decided to turn professional.

[2] He also participated in the Universiade hosted by his hometown and won silver in the individual event.

[3] In 2005 he reached the final of the Seoul Grand Prix and was defeated by his rookie national teammate Kim Jung-hwan.

[4][5] At the 2007 FIE World Championships he won the bronze medal in the men's individual sabre category after losing to four-time Olympic champion and ten-time world champion Stanislav Pozdnyakov of Russia 12–15 in the semifinals.

A week later, they successfully defended their team gold medal at the Asian Championships, his last major international competition.