The battalion was reactivated on 1 October 1949 at Camp Pendleton and assigned to the 1st Marine Division. It was then reassigned during July 1950 to the 1st Provisional Marine Brigade. The battalion was then deployed in July and August 1950 to Pusan in Korea. The battalion participated in the Korean War, from August 1950 to July 1953, taking part in the actions at the Battle of the Pusan Perimeter, at Inchon and the Chosin Reservoir. Personnel also saw action on the East-Central and Western Fronts.