355th

355th may refer to:


 * 355th Fighter Squadron, an inactive United States Air Force unit
 * 355th Fighter Wing, a United States Air Force unit assigned to the Air Combat Command's Twelfth Air Force
 * 355th Infantry Regiment (United States), an infantry regiment of the United States Army
 * 355th Operations Group, a United States Air Force unit, assigned to the 355th Wing
 * 355th Troop Carrier Squadron, an inactive United States Air Force unit