381st

381st may refer to:


 * 381st Bombardment Squadron, inactive United States Air Force unit
 * 381st Fighter Squadron or 18th Reconnaissance Squadron, squadron of the United States Air Force
 * 381st Intelligence Squadron, intelligence unit located at Joint Base Elmendorf-Richardson, Alaska
 * 381st Training Group at Vandenberg AFB, California provides training for the nation's space and intercontinental ballistic missile (ICBM) operations