The 25th Battalion (Nova Scotia Rifles), CEF (also known as "MacKenzie Battalion", "Master Raiders", "Raiding Battalion") was a unit in the Canadian Expeditionary Force during the Great War. 

It was the second infantry battalion (after the 17th) of ten to be raised in Nova Scotia during the war. 

The 25th served in Belgium and France as part of the 5th Canadian Brigade, 2nd Canadian Division from 16 September 1915 until the end of the war. Regimental headquarters were established at the Halifax Armouries, with recruitment offices in Sydney, Amherst, New Glasgow, Truro and Yarmouth. Of the 1000 Nova Scotians that started with the battalion, after the first year of fighting, 100 were left in the battalion, while 900 men were killed, taken prisoner, missing or injured.

The 25th Battalion was authorized on 7 November 1914 and embarked for Great Britain on 20 May 1915. The battalion was disbanded on 15 September 1920.

The 25th Battalion recruited throughout Nova Scotia and was mobilized at Halifax