The 103rd Battalion, CEF, was an infantry battalion of the Great War Canadian Expeditionary Force. The 103rd Battalion was authorized on 22 December 1915 and embarked for Britain on 23 July 1916 aboard HMT Olympic. There, it provided reinforcements for the Canadian Corps in the field until 7 January 1917, when its personnel were absorbed by the 16th Reserve Battalion, CEF. The battalion disbanded on 1 September 1917.