III MEF Support Battalion

Who we are

III Marine Expeditionary Force (MEF) Support Battalion provides and coordinates direct combat service support (CSS), security, and administrative services to III Marine Expeditionary Force (MEF), 3d Marine Expeditionary Brigade (MEB), and III MEF Information Group (MIG) Command Elements (CE) in order to enable III MEF to win in competition and conflict.

Featured News

31st MEU Supports Anti-Submarine Warfare Operation in Indo-Pacific

On Aug. 8, 2025, Marine Medium Tiltrotor Squadron 265 (Reinforced), 31st Marine Expeditionary Unit (MEU), supported an operational anti-submarine warfare (ASW) mission utilizing the MV-22B Osprey teamed with two Navy MH-60R Sea Hawk helicopters to distribute sonobuoys. This iteration of anti-submarine operations represents the first time a forward-deployed MV-22B assigned to the 31st MEU has operated in an ASW role within the Indo-Pacific theater, significantly enhancing the 31st MEU’s capabilities and contributing to regional maritime security.

3/12 Executes HIMARS Dry-Fire Training at Camp Fuji

COMBINED ARMS TRAINING CENTER, CAMP FUJI, Japan – U.S. Marines with 3d Battalion, 12th Marine Regiment, 3d Marine Division conducted High Mobility Artillery Rocket System (HIMARS) dry-fire training at Combined Arms Training Center (CATC) Camp Fuji from June 11-13, 2025. This training represents a significant enhancement of Camp Fuji’s capability to support long-range fires and reflects our commitment to maintaining readiness and deterrence in the Indo-Pacific alongside our Japanese partners.

3d Radio Battalion Change of Command

MARINE CORPS BASE HAWAII, Hawaii - On 18 June 2025, 3d Radio Battalion bid fair winds and following seas to Lieutenant Colonel Gary A. Keefer, and welcomed Lieutenant Colonel Sean F. X. Barrett to the family. Lieutenant Colonel Keefer was the Battalion Commander of 3d Radio Battalion for three years and will be retiring after 23 years of faithful service. Lieutenant Colonel Barrett is assuming command of 3d Radio Battalion after serving consecutive assignments at I Marine Expeditionary Force G-2.