The Honourable St John Brodrick (c. 1685 – 21 February 1728), was an Anglo-Irish politician who sat in the Irish House of Commons from 1709 to 1728 and in the British House of Commons from 1721 to 1727. Brodrick was a son of Alan Brodrick, 1st Viscount Midleton and brother of Alan Brodrick, 2nd Viscount Midleton; his mother was his father's first wife, Catherine Barry, daughter of Redmond Barry of Rathcormac. He predeceased his father by some months.