Eielson Air Force Base (IATA: EIL, ICAO: PAEI, FAA LID: EIL) is a United States Air Force (USAF) base located approximately 26 miles (42 km) southeast of Fairbanks, Alaska, and just southeast of Moose Creek, Alaska. It was established in 1943 as Mile 26 Satellite Field and redesignated Eielson Air Force Base on 13 January 1948. It has been a Superfund site since 1989. Eielson AFB was named in honor of polar pilot Carl Ben Eielson.

Its host unit is the 354th Fighter Wing (354 FW) assigned to the Eleventh Air Force of the Pacific Air Forces. The 354 FW's primary mission is to support RED FLAG-Alaska, a series of Pacific Air Forces commander–directed field training exercises for U.S. Forces, joint offensive counter-air, interdiction, close-air support, and large force employment training in a simulated combat environment. These exercises are conducted on the Joint Pacific Alaskan Range Complex (JPARC) with air operations flown out of Eielson and its sister installation, Joint Base Elmendorf–Richardson (the former Elmendorf Air Force Base).

Eielson projects to have 54 Lockheed Martin F-35 Lightning II combat aircraft assigned to the installation, of which the first two aircraft arrived on 21 April 2020. The last of the aircraft arrived in April 2022. The planes come with an estimated 3,500 personnel, to include airmen and their families as well as civilian personnel.