Lee was included in South Korea's squad for the 2014 FIFA World Cup by showing good performances with three goals in the final round of the qualification. In their first group stage match against Russia on 17 June 2014, he came on as a substitute for Park Chu-young in the 52nd minute and scored his first ever World Cup goal in a 1–1 draw when his shot from outside the box was spilled by goalkeeper Igor Akinfeev over his head and over the line. He also assisted Koo Ja-cheol's goal in the second match against Algeria.