Alexander Gordon (9 June 1841–21 February 1931) was an English Unitarian minister and religious historian. A prolific contributor to the Dictionary of National Biography, he wrote for it well over seven hundred articles dealing mainly with nonconformists.
He was born in Coventry, the son of John Gordon, a Unitarian minister. He was an undergraduate at Edinburgh University from 1856 to 1859, then trained at Manchester New College in London, and studied under Ignaz von Döllinger in Munich. He was a minister at Aberdeen and Norwich, before settling in Belfast in 1877 at its First Presbyterian Church. He was Principal of the Unitarian Home Missionary College, Manchester, from 1890 to 1911.