514th may refer to:
514th Air Defense Group, disbanded United States Air Force (USAF) organization 514th Air Mobility Wing, wing of the United States Air Force based out of Joint Base McGuire-Dix-Lakehurst, New Jersey 514th Fighter-Interceptor Squadron, inactive United States Air Force unit 514th Flight Test Squadron (514 FLTS), part of the Ogden Air Logistics Center based at Hill Air Force Base, Utah 514th Troop Carrier Group or 514th Operations Group, United States Air Force Reserve unit, assigned to the 514th Air Mobility Wing
See also 514 (number) 514, the year 514 (DXIV) of the Julian calendar 514 BC