Do Kyung-soo (born ()January 12, 1993), better known by his stage name D.O., is a South Korean singer and actor. He is best known as a member and one of the main vocalists of the South Korean-Chinese boy group EXO. Apart from his group's activities, D.O. has also starred in various television dramas and movies such as Pure Love (2016) and My Annoying Brother (2016).
D.O. was born in Goyang, Gyeonggi Province, South Korea, on January 12, 1993. He went to Goyang Poongsan Elementary School, Baekshin Middle School, and Baekseok High School. He has an older brother, Do Seungsoo, who is 3 years older than him. D.O. began singing in primary school and was an avid participant in local singing competitions throughout his high school career.
In 2010, he was advised to audition for S.M. Entertainment after winning a local singing contest. He subsequently became an S.M. Entertainment trainee during his last two years of high school. He performed Na Yoon-kwon's "Anticipation" and Brown Eyed Soul's "My Story" at his S.M. audition.