MEF may stand for:
Government Ministry of Economy and Finance (Peru), the Peruvian ministry of economics and finance Ministry of Economy and Finance (Uruguay), the Uruguayan ministry of economics and finance Ministry of Economy and Finance (Italy), the Italian ministry of economics and finance Ministry of Environment and Forests, India Mission Essential Functions, critical operations of the US government in the face of unexpected disruption
Military Malaita Eagle Force, a militant organization originating in the island of Malaita in the Solomon Islands Marine Expeditionary Force, one of the major deployable subdivisions of the United States Marine Corps Mediterranean Expeditionary Force Mesopotamian Expeditionary Force during the First World War
Organizations Mahratta Education Fund, Indian non-profit organisation Major Economies Forum on Energy and Climate Change Media Education Foundation MEF International School Istanbul Middle East Forum, an American conservative think tank Mongolia Economic Forum, Mongolia
Science/technology Managed Extensibility Framework, a software plugin framework, written by Microsoft Maximum Elevation Figure (flying) Maximal expiratory flow, another name for peak expiratory flow in spirometry Medial eye fields Metro Ethernet Forum Modernized e-File (MeF), an electronic system for filing U.S. income taxes Modified Energy Factor (Energy Star Rating Value, US Department of Energy (DOE)) Mouse embryonic fibroblast Museo Paleontológico Egidio Feruglio collection code Mef2 (myocyte enhancer factor-2), a family of gene transcription factors Multiscale Electrophysiology Format, a data format used in electrophysiology
Transport Mei Foo station, Hong Kong, MTR station code