Dr. Yong Sik Yoon is a colorectal surgeon and a professor at the Department of Surgery of the University of Ulsan College Medicine (UUCM). He is certificated by the Korean Board of Surgery and the Korean Society of Coloproctology. He earned his medical degree from UUCM. He completed his internship, residency, and fellowship at the Asan Medical Center (AMC), which is an educational hospital of UUCM. From 2010, he started his own practice as clinical assistant professor at AMC.