Thomas Bruce, 2nd Earl of Ailesbury (later styled Aylesbury) and 3rd Earl of Elgin (1656 – 16 December 1741), styled Lord Bruce between 1663 and 1685, was an English politician and memoirist. He was the son of Robert Bruce, 2nd Earl of Elgin, and Lady Diana Grey. His maternal grandparents were Henry Grey, 1st Earl of Stamford, and Lady Anne Cecil, daughter of William Cecil, 2nd Earl of Exeter. His Memoirs, which were not published until long after his death, are a valuable source for English history in the last quarter of the seventeenth century.