Major-General Ewen George Sinclair-Maclagan, CB, CMG, DSO (24 December 1868–24 November 1948) was an officer in the British Army who fought in British India and the Second Boer War. He was later seconded to the Australian Army and served with the Australian Imperial Force during the First World War. During the latter stages of the war, he commanded the 4th Australian Division. After the war he returned to service with the British Army.