On 29 June 2007, Lee made his senior team debut in a friendly against Iraq through substitution in the second half. Lee also managed to score his debut goal from an assist made by Lee Chun-Soo. On 15 October 2008, Lee scored two goals in a qualification match of the 2010 FIFA World Cup against United Arab Emirates. On 19 November 2008, Lee scored the most important goal in his international career yet in an away game against Saudi Arabia, which ended South Korea's nineteen-year losing spell against the Saudis. Although he played in most of the qualification campaign, he was not named for the team to participate in the 2010 World Cup.