[1][2] After retiring, he became a sports commentator for Seoul Broadcasting System and covered fencing events at various international tournaments.

At the sabre 2010 World Fencing Championships, he won the gold medal, beating then-world number 1 Nicolas Limbach 15–9 in the final.

[5][6] Won, together with Oh Eun-seok, Kim Jung-hwan and Gu Bon-gil, were selected for the national team to compete at the 2012 Summer Olympics[7] The Olympics began on a sour note for them as he, Kim and Gu all did not make it past the semi-final stage of the individual event; he lost in the last 16 to Nikolay Kovalev, the eventual bronze medallist.

[4] In 2016 Won was awarded the Order of Sports Merit Cheongnyong (청룡장; English: Blue Dragon) class, the South Korean government's highest honor bestowed on professional athletes who meet the criteria.

[4][17] In November 2021, ahead of the Orleans Grand Prix, the Korean Fencing Federation announced that Won had been appointed coach of the men's sabre team.