309th may refer to:
309th Aerospace Maintenance and Regeneration Group, a United States Air Force storage and maintenance facility in Tucson, Arizona 309th Air Division, inactive United States Air Force organization 309th Airlift Squadron, part of the 86th Airlift Wing at Chièvres Air Base, Belgium 309th Bombardment Squadron or 525th Fighter Squadron, United States Air Force unit 309th Fighter Squadron (309 FS), part of the 56th Operations Group at Luke Air Force Base, Arizona 309th Maintenance Wing, inactive wing of the United States Air Force last based at Hill Air Force Base, Utah 309th Military Intelligence Battalion (United States) conducts initial entry, collective, and functional training 309th Rifle Division (Soviet Union), formed for the first time as a standard Red Army rifle division shortly after the German invasion
See also 309 (number) 309, the year 309 (CCCIX) of the Julian calendar 309 BC