Lee met actor Ji Sung on the set of 2004 TV series Save Last Dance for Me, and they confirmed their relationship in 2007. On August 2, 2013, they announced their engagement by uploading handwritten letters on their respective official fan sites. They married at Aston House, W Seoul Walkerhill Hotel on September 27, 2013. Their first child, daughter Kwak Ji-yoo was born on June 12, 2015.