25th Regiment may refer to:
Infantry regiments 25th Infantry Regiment (Argentina) 25th Independent Mixed Regiment, a Japanese unit 25th Infantry Regiment (United States) 25th Regiment of Foot, a British Army unit 25th Punjabis, a British Indian Army unit 25th Continental Regiment, a unit during the American Revolutionary War Units during the American Civil War 25th Arkansas Infantry Regiment, a Confederate Army unit Union Army 25th Connecticut Infantry Regiment 25th Illinois Infantry Regiment 25th Indiana Infantry Regiment 25th Iowa Infantry Regiment 25th Massachusetts Infantry Regiment 25th Kentucky Infantry Regiment 25th Maine Infantry Regiment 25th Michigan Infantry Regiment 25th New Jersey Infantry Regiment 25th New York Infantry Regiment 25th Wisconsin Infantry Regiment
Other regiments 25th Aviation Regiment (United States) 25th Dragoons, a British Army cavalry unit 25th Field Artillery Regiment, United States 25th Greater Poland Uhlan Regiment 25th SS Police Regiment, Germany
See also 25th Army (disambiguation) 25th Brigade (disambiguation) XXV Corps (disambiguation) 25 Squadron (disambiguation)