3rd Regiment

The 3rd Regiment may refer to many military units.

British Army

• 3rd Regiment of Foot = The Buffs (Royal East Kent Regiment)
• 3rd Regiment of Foot Guards = Scots Guards
• 3rd Regiment Royal Horse Artillery

Norwegian Army

• 3rd Infantry Regiment (Norway)

Philippine Commonwealth Army

• 3rd Infantry Regiment (Philippine Commonwealth Army)

Philippine Constabulary

• 3rd Infantry Regiment (Philippine Constabulary) - The 3rd Infantry Regiment, Philippine Constabulary was the military establishment and active on 1935 to 1942 and 1944 to 1946 as the military command of the United States of America and stationed in Central Luzon.

United States Army

• 3rd Armored Cavalry Regiment (United States)
• 3rd Aviation Regiment (United States)
• 3rd Infantry Regiment (United States)
• 3rd Regiment Illinois Volunteer Cavalry
• 3rd Regiment Iowa Volunteer Cavalry
• 3rd Regiment Indiana Cavalry
• 3rd Regiment Kentucky Volunteer Cavalry
• 3rd Regiment Kentucky Volunteer Infantry
• 3rd Regiment South Carolina Volunteer Infantry (African Descent)