After graduating from Kyung Hee University in 2002, Lee started his professional career at a K League club Anyang LG Cheetahs.

(renamed FC Seoul since 2004) He was originally a forward, but Anyang's manager Cho Kwang-rae advised him to change his role to a defender.

[3] In the 2011 AFC Champions League semi-final first leg against his former club Suwon, Lee was involved in a heated argument with Al-Sadd teammates following Mamadou Niang's controversial second goal, which was scored after Suwon claimed to have put the ball out to allow treatment to injured players, thus inferring possession should have been returned to the Korean club.

The situation prompted Lee to walk off the pitch requiring his manager Jorge Fossati to substitute him with Ibrahim Majid for the remainder of additional time.

Lee was one of South Korea's major contributors when his country reached the knockout stage in the 2010 FIFA World Cup.