MGCIS-1 was alerted for duty in Korea on 5 July 1950 and reassigned to Marine Aircraft Group 33 the following day. At the outbreak of the war, MGCIS-1 was severely under strength. Additional Marines were joined from other squadrons within Marine Air Control Group 2 to fill out the squadron's ranks prior to deployment. The squadron departed Long Beach Harbor on 14 July 1950 on board . They arrived in Kobe, Japan on 1 August 1950 and set up operations at Itami Air Force Base, Honshu, Japan to be co-located with VMF(N)-513.