Lee Beom-soo debuted as an actor in the 1990 film Well, Sometimes Let’s Look at the Sky and shot to fame with his role in the 2003 rom-com movie Singles. In 2006, he joined the action-thriller film The City of Violence, which won him two Best Supporting Actor trophies. In 2007, he acted alongside Lee Yo-won in the hit SBS medical drama Surgeon Bong Dal Hee, which gave him the Baeksang Popularity Award. He followed this up with another high-rating SBS drama titled On Air, where he played a manager of a top star. In 2010, he led the cast of Giant, which was named Best Drama at the SBS Drama Awards. He also took home numerous acting citations for his work in the series. In 2013, he starred in the KBS2 dramas IRIS 2 and Prime Minister and I. In 2016, he worked with Lee Jung-jae and Liam Neeson in the war drama film Operation Chromite, which earned him the Popularity Award at the 53rd Grand Bell Awards.

Lee Beom-soo tied the knot with an English interpreter named Lee Yun-jin in 2010. They first met in 2008 when she taught the actor English. They have two children together.