Reverend John de la Poer Beresford, 4th Marquess of Waterford (27 April 1814 – 6 November 1866) was an Irish peer and Church of Ireland minister. Beresford was the third son of the Henry Beresford, 2nd Marquess of Waterford and his wife, . He was educated at Eton and Trinity College, Cambridge. He later entered the ministry and was the incumbent of Mullaghbrack, County Armagh and a Prebendary of St Patrick's Cathedral, serving under his uncle, Lord John. On 20 February 1843, he married Christiana Leslie, daughter of Charles Powell Leslie II. They had five sons: