Lee Ok-Sung (born February 7, 1981 in Jinju, Gyeongsangnam-do, South Korea ) is a South Korean amateur boxer best known for winning the 2005 World Championships at flyweight.
Lee is relatively tall for a flyweight (170cm).
At the 2005 World Championships
, he beat young southpaw Rau'shee Warren
to set up his surprise championship win.
In the finals he defeated Cuban Andry Laffita
who had beaten Somjit Jongjohor
(THA) and Jérôme Thomas
(FRA). He became the first South Korean
amateur boxer to win a gold medal at the World Amateur Boxing Championships
when Moon Sung-Kil
won the gold in Reno
, United States
At the 2006 Asian Games Lee just as surprisingly lost to Yang Bo of China in the quarterfinals, and his winning streak in international competition ended at 28 games.
He didn't participated in the national trials for the 2007 World Championships in order to complete his Master's degree.
In the first round of the 2008 Olympic Games Lee defeated 2007 World Champion Rau'shee Warren in another surprising upset victory.