Lee Ok-Sung (b. Feb 7, 1981) is a South Korean amateur boxer best known for winning the 2005 World Championships at flyweight.
At the Asian Games 2006 he surprisingly lost to Chinese boxer Yang Bo. Lee is qualified in the flyweight class for the 2008 Beijing Olympics.
World Amateur championships results
- Defeated Igor Samolenko (Moldova) 30-20
- Defeated Nikoloz Izoria (Georgia) 26-17
- Defeated Anvar Yunusov (Tajikistan) 15-9
- Defeated Rau'shee Warren (United States) 44-27
- Defeated Andry Laffita (Cuba) 33-22
2008 (as a flyweight)