In August 2011 Lee was selected as a member of the South Korean U-18 national team for the Asian Junior Baseball Championship held in Yokohama, Japan.
He started Team Korea's third game of the round robin phase against Thailand and pitched two scoreless innings with four strikeouts en route to a 20–0 win.
In the 2012 KBO Draft, Lee was selected by the NC Dinos as the first overall pick, along with No Sung-ho.
Though Lee compiled a decent record of 9–9 with two saves both as a starter and reliever in the 2016 season, his ERA dipped again to 5.51.
This biographical article relating to a South Korean baseball figure is a stub.