Marquess of the County of Bute, shortened in general usage to Marquess of Bute, is a title in the Peerage of Great Britain. It was created in 1796 for John Stuart, 4th Earl of Bute.

John Stuart, 1st Marquess of Bute PC, FRS, styled Lord Mount Stuart until 1792 and known as The Earl of Bute between 1792 and 1794, was a British nobleman, coalfield owner, diplomat and politician who sat in the House of Commons from 1766 to 1776.