Alexander Stewart, 2nd Earl of Buchan (died 1505) was the only son of James Stewart, 1st Earl of Buchan, and Margaret Ogilvy. Alexander succeeded to the Earldom and the and other lands, probably in 1499, as he got sasine of the Earldom on 23 January 1499/1500. On 21 January 1490/1491 he got from his father a Charter to himself and his first wife, Isobel Ogilvy, of the lands of the Barony of Kettins and others; and on 6 February 1499/1500, another of the same lands to himself and his second wife, Margaret Ruthven. The Earl died in 1505.