William Thomas Brownlow Cecil, 5th Marquess of Exeter, (27 October 1876 – 1956), known as Lord Burghley from 1895 to 1898, was a British peer.
Exeter was the son of Brownlow Cecil, 4th Marquess of Exeter, and his wife, the former Isabella Whichcote.
He was educated at Eton and Magdalene College, Cambridge.
In 1899 he acted temporarily as aide-de-camp to Major-General John Edward Boyes, with the 7th Brigade at Aldershot.