125th Regiment may refer to:
125th Field Artillery Regiment, United States 125th Guards Bomber Aviation Regiment, Soviet Union 125th Infantry Regiment (United States) 125th Napier's Rifles, British Indian Army 125th Regiment of Foot, British Army
American Civil War regiments 125th Illinois Infantry Regiment 125th New York Infantry Regiment 125th Ohio Infantry Regiment 125th Pennsylvania Infantry Regiment 125th United States Colored Infantry Regiment
See also 125th Brigade (disambiguation) 125th Division (disambiguation) 125th (disambiguation)