William Augustus McIlroy (1873-1942) was a Presbyterian/United Church minister in Ontario. He was born in Kingston, graduated from Queen's University and was ordained a minister of the Presbyterian Church in 1900. He served charges at Williamsburg, Winchester Springs, Stewarton Presbyterian Church, Ottawa, and St. Giles' Church, Hamilton. As well, he was called to Bond Street United Church in 1928 and brought that church into amalgamation with St. James' United Church, resulting in St. James-Bond United Church. After leaving the active ministry, he served as the first Executive Secretary of the Prisoner's Rehabilitation Society (later known as the John Howard Society). Rev. McIlroy died in 1942. He was the father of Thora McIlroy Mills, and the grandfather of Rev. Dr. Howard McIlroy Mills and Diane Rogers.