III Marine Expeditionary Force (III MEF) is a formation of the Marine Air-Ground Task Force of the United States Marine Corps. It is forward-deployed and able to rapidly conduct operations across the spectrum from humanitarian assistance and disaster relief (HA/DR) to amphibious assault and high-intensity combat.

It maintains a forward presence in Japan and Asia to support the Treaty of Mutual Cooperation and Security between the United States and Japan (1960) and other alliance relationships of the United States. III MEF also conducts combined operations and training throughout the region in support of the National Security Strategy for Theater Security Cooperation.

The Marines and sailors of III MEF engage in more than 65 combined, bilateral and multilateral training exercises annually throughout the Asia-Pacific region, in countries including treaty allies Japan, Thailand, South Korea, the Philippines, and Australia. These exercises build partner capacity, develop and maintain strong regional alliances and military-to-military contacts. These exercises prepare III MEF to conduct operations ranging from major combat operations to humanitarian assistance and disaster relief.

III MEF has played a significant role in humanitarian assistance and disaster relief missions throughout the region. The MEF assisted the relief efforts led by the Government of Japan during Operation Tomodachi after the 2011 Tōhoku earthquake and tsunami. III MEF also conducted HA/DR missions in Thailand in October 2011, the Philippines in October 2010, and Indonesia in October 2009. Most recently in response to the resulting humanitarian crisis from Typhoon Haiyan which struck the Philippines in 2013, III MEF activated as Joint Task Force 505 to conduct humanitarian assistance and disaster relief operations in support of the Philippine government. More than 2,495 tons of relief supplies were delivered, and over 21,000 people were evacuated.

Mission

Commanded by a lieutenant general with its headquarters at Camp Courtney, III MEF's mission is to provide forward based and deployed forces to the commander, U.S. Indo-Pacific Command, to conduct Phase 0 engagement and theater security cooperation events, support contingencies and emergent requirements, and prepare to rapidly execute existing operations plans in support of the theater and national military strategies.

III MEF is organized as a Marine Air Ground Task Force (MAGTF) to provide a rapidly deployable, flexible self-contained fighting force. The Marines combine air, ground, and logistics forces to operate as a coherent, self-sufficient force. Each mission dictates the MAGTF's scale and structure, giving the Marine Corps the flexibility to respond to any crisis and making a "force in readiness." A MEF is the largest of all MAGTFs.

Organization

thumb|center|1024px|III Marine Expeditionary Force organization as of May 2026 (click to enlarge)

Units

III Marine Expeditionary Force, together with I Marine Expeditionary Force, makes up Marine Forces, Pacific.

  • Ground combat element: 3rd Marine Division
  • Aviation combat element: 1st Marine Aircraft Wing
  • Logistics combat element: 3rd Marine Logistics Group
  • Command element: III Marine Expeditionary Force Information Group
  • III MEF Support Battalion
  • 3rd Intelligence Battalion
  • 3rd Radio Battalion
  • 7th Communication Battalion
  • 5th Air Naval Gunfire Liaison Company (ANGLICO)
  • 3rd Marine Expeditionary Brigade
  • 31st Marine Expeditionary Unit

III MEF Band

As the Eastern Hemisphere’s sole musical representative of the United States Marine Corps, the III MEF Band enjoys a busy schedule filled with performances across Okinawa and the Indo-Pacific region each year. The band capitalizes on this unique position by making it a priority to present community outreach performances and by participating in bi-lateral engagements with partner and allied nations throughout Asia and the Pacific. Consisting of musicians trained in a variety of musical styles, the III MEF Band is able to provide a number of small ensembles for civilian events, including brass and woodwind quintets, jazz combo, rock band, and brass band. The band was awarded the title of 2018 Marine Corps Band of the Year in February 2018. The III MEF Band was most recently award the 2023 Colonel George S. Howard Citation of Musical Excellence for Military Concert Bands.

The following comprises the leadership of the band:

  • Band Officer – Captain Randel Metzinger
  • Enlisted Bandleader – Master Sergeant James Holt
  • Instrument Repair Technician – Gunnery Sergeant Mathew Medina
  • Enlisted Conductor – Gunnery Sergeant Martin Arreola Jr
  • Drum Major – Staff Sergeant Peter Yurkovich
  • Production Manager – Gunnery Sergeant Joshua W. Waldie

Uniquely, the band used to have its own mascot. The history of the use of a mascot dates back to 1974, when the Commanding General of the 1st Marine Aircraft Wing presented a Golden Retriever to the 1st MAW Band. Since then, the 1st MAW and 3D MARDIV Bands combined to form the III MEF Band and five mascots have served the unit. Since November of 2012, Sgt Chopper V continued this unique tradition and retired in 2024 after serving the Marines of the III MEF Band faithfully and honorably.

Locations and units

Japan

Okinawa

  • Marine Corps Base Camp Smedley D. Butler
  • Marine Corps Air Station Futenma
  • III Marine Expeditionary Force Command Element (III MEF CE)
  • III Marine Expeditionary Force Headquarters Group (III MHG)
  • III Marine Expeditionary Force Headquarters and Service Company (III MEF HQSVC)
  • 3rd Marine Expeditionary Brigade (3rd MEB)
  • 3rd Marine Division (3rd MarDiv)
  • 1st Marine Aircraft Wing (1st MAW)
  • 3rd Marine Logistics Group (3rd MLG)
  • 31st Marine Expeditionary Unit (31st MEU)

Honshu

  • Camp Fuji
  • Marine Corps Air Station Iwakuni
  • Marine Aircraft Group 12
  • Combat Logistics Company 36

United States

Hawaii

  • Marine Corps Air Station Kaneohe Bay
  • 3rd Marine Regiment
  • Marine Aircraft Group 24
  • Combat Logistics Battalion 3
  • Combat Logistics Company 33
  • Combat Logistics Company 35

South Korea

  • Camp Mujuk

List of commanders

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Awards and decorations

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||Navy Unit Commendation Streamer with two Bronze Stars