Do Sang-woo started out as a model. He made his acting debut with a minor role in the 2011 tvN series Flower Boy Ramyun Shop. In 2014, he played Gong Hyo-jin’s cheating boyfriend in the SBS medical romance It’s Okay, It’s Love. In 2015, he bagged the Fashionista Award at the 10th Asia Model Awards. That same year, he was cast in a main role in the MBC family series My Daughter, Geum Sa-wol. His performance in the drama earned him a Best New Actor nomination at the 34th MBC Drama Awards. In 2019, he joined the main cast of TV Chosun’s fantasy sageuk Queen: Love and War. In 2020, he appeared in the SBS romantic comedy Backstreet Rookie.
Do Sang-woo began his mandatory military service on April 5, 2016. He was discharged in January 2018. He dated his Legendary Witch co-star Kim Yoon-seo. The couple broke up in 2019.