Cameron was commissioned a second lieutenant in the Grenadier Guards on 5 September 1896, and promoted to lieutenant on 8 September 1898. He served in South Africa 1899-1900 during the Second Boer War, where he was part of the Kimberley relief force, and was wounded at the battle of Belmont (November 1899). He was again in South Africa for the end of the war, and was invalided home in July 1902, when he left Cape Town on the SS "Canada", returning to Southampton.