Lee Sang-woo made his acting debut in an episode of KBS2’s Drama City in 2005. In 2007, he appeared in the SBS series First Wives’ Club, which earned him the New Star Award at the SBS Drama Awards. He also bagged a Best New Actor for TV nomination at the 45th Baeksang Arts Awards for his work in the drama. In 2011, he was nominated for an Excellence Award at the SBS Drama Awards for the melodrama Thousand Day Promise. In 2012, he took home an Excellence Award at the MBC Drama Awards for his work in Feast of the Gods and The Horse Healer. In 2016, he starred in the MBC family drama All’s Well With a Happy Home, which won him a Top Excellence Award at the MBC Drama Awards. In 2018, he acted alongside Han Ji-hye in the KBS2 series Shall We Live Together, which gave him acting trophies at the 6th APAN Star Awards and the KBS Drama Awards. In 2019, he and Han Ji-hye reunited in the MBC legal drama Golden Garden, which scored him a Top Excellence Award at the MBC Drama Awards.

Lee Sang-woo and his All’s Well With a Happy Home co-star Kim So-yeon tied the knot in June 2017. Their relationship was first confirmed on September 6, 2016.