Yoon Doo-joon was born in Goyang, South Korea on July 4, 1989. His dream of becoming a high school Physical Education teacher changed suddenly during his second year of high school after watching MTV's Big Bang Documentary. His parents and teachers didn't agree with him at first. However, he pleaded to them to register him for Music school and soon started auditioning to become a singer. Yoon then became a trainee of JYP Entertainment and was featured in the Mnet documentary Hot Blooded Men, a reality program that shows the preparation for their debut, with 2AM and 2PM, but he was eliminated along the course of the show. He then moved to Cube Entertainment and was featured as a rapper in AJ's "Wipe the Tears". After his debut with the group, he became part of Danbi and debuted as an actor through More Charming by the Day and All My Love. He finally debuted as the leader of Beast. Their journey leading up to debut was showcased in their MTV documentary MTV B2ST. He currently attends at Dongshin University as a student majoring in Broadcast Entertainment, under a full scholarship, along with 4 other members of Beast.