He had undergone surgery and was officially discharged on June 7, 2006. The decision was made by the military when Won Bin sustained injury to his ACL. On June 2, 2006, the military officially confirmed that Won Bin would be no longer active. After graduating from the Graduate School of Arts in Yong-In University in 2005, Won Bin started his military duty in November 2005 and stationed at the Korean Demilitarized Zone, a position for which he volunteered. His career was interrupted by his mandatory service to the South Korean Army. Taegukgi was the best selling film in South Korea in 2004 with 11.75 million admissions. With the success of the critically acclaimed Taegukgi, recognition of his acting skills has reached an ever-wider international audience. Won Bin also had roles in a number of popular films, including Guns & Talks and My Brother, but it is his portrayal of the sensitive younger brother in the blockbuster war film Taegukgi (2004) that cemented his international fame. In 2002, Won Bin was involved in the first South Korea and Japan joint production drama Friends. Autumn in My Heart gained wide popularity in Asia and he became one of the most popular Korean actors in Korea and Asia as well. His role as a rebellious youngest son in Kkokji proved his acting potential and his role in the widely successful drama landed him on the A-list for Korean performers.
He made his big breakthrough in 2000 with drama Tough Guy's Love ( Kkokji) and Autumn in My Heart.
In 1999, Won Bin came back to the screen with a lead role in drama Kwangki from which he was recognized as a promising young actor and a teen heartthrob. After Ready Go!, he took a break and entered a college called Paekche Institute of the Arts in 1998 to take acting classes. His role in Ready Go! (1998) helped hone his acting chops. Won Bin made his screen debut with a supporting role in the 1997 drama film Propose. The following month, Won Bin signed an acting contract with a talent agency. He started to take acting classes at the station's headquarters and appeared in several dramas. In November 1995, a cable television station was looking to recruit and hire new actors Won Bin applied and was accepted in his last semester of high school. Won Bin graduated from a mechanical high school, where he studied car repair and mechanics. As a young boy, he initially planned to become a car mechanic due to his interest in car racing and motorcycling. Won Bin started taekwondo lessons and now holds a black belt. While not talkative or outgoing, he excelled at athletics. As was common for other children living in mountainous regions, Won Bin spent most of his time playing around with friends in the mountains and rivers, and later explained: "I came back home most nights at sunset with a black and dusty face." He was frequently shy, introspective, and quiet, character traits that would continue to follow him throughout adulthood. His father was formerly employed in a mine and his mother worked on a farm both of his parents are now retired. He is the fifth and youngest child, with one brother and three sisters. Won Bin was born and raised in Jeongseon County in Gangwon Province, South Korea.