Republic of Korea Army

The Republic of Korea Army, also called the ROK Army or South Korean Army, is the ground warfare branch of the Republic of Korea Armed Forces and the largest of South Korea's military branches, with about 400,000 members as of 2025. That size is kept up through conscription, since able-bodied South Korean men must complete military service, which in the army lasts 18 months. The force traces its modern form to the Korean Constabulary of 1945, which drew heavily on Imperial Japanese Army doctrine and former personnel, a legacy that remains controversial in South Korea. It was pushed close to defeat by the North Korean offensives that opened the Korean War, then rebuilt with United States training and equipment, and later sent roughly 320,000 combat troops to Vietnam and served alongside coalition forces in the Gulf War, Iraq and Afghanistan. Today it is organised into two field armies, six corps and 34 divisions.