Lee Dong-gun made his debut in the entertainment industry in 1998 as a singer, but he would later gain fame as an actor, starring in television dramas such as Sweet 18, Lovers in Paris, and Stained Glass.

During a fan meeting event in Japan held on 5 December 2005, Lee announced the release of his first photobook which also included a making-of DVD, poster and postcard.

This large-scale event was intended to promote Korean culture across Asia and expected to bring in 150,000 tourists to stimulate the local economy.

This two-day event from 14 to 15 August 2007, featured Korean celebrities with large fanbases and was intended as a cultural exchange program between Korea and Japan.

[23] In the historical drama Queen for Seven Days, Lee impressed viewers with his a wide range of emotions and acting performance with his role as the tyrannical Joseon ruler Yeonsangun.

[31] Lee enlisted for his mandatory military service on 15 June 2010 at the 102 Reserves in Chuncheon, Gangwon Province for four weeks of basic training followed by 21 months of active duty.

[33] He was discharged on 28 March 2012, and on the same day, he was appointed promotional ambassador for the 2012 Korean Formula One Grand Prix held at the Korea International Circuit in October.