The 205th (Tiger) Battalion, CEF was a unit in the Canadian Expeditionary Force during the First World War. Established in late 1915, it was stationed in Hamilton, Ontario and began recruiting toward the end of February 1916. In late 1916, the unit was redesignated a machine gun battalion, but a few months later, in April 1917, the 205th (Tiger) Battalion was broken up for drafts. One company (250 men) was transferred to the 164th (Halton and Dufferin) Battalion, CEF, which was recruiting in nearby Halton County. The unit continued to exist as the 205th Machine Gun Depot and then the 205th Machine Gun School.