133rd Regiment may refer to:
133rd Field Artillery Regiment, United States 133rd Light Anti-Aircraft Regiment, Royal Artillery 133rd Infantry Regiment (United States) 133rd Regiment of Foot, Britain 133rd Tank Regiment, Italy
American Civil War regiments 133rd Illinois Infantry Regiment 133rd Indiana Infantry Regiment 133rd New York Infantry Regiment 133rd Ohio Infantry Regiment 133rd Pennsylvania Infantry Regiment
See also 133rd Division (disambiguation)