John Stuart, the 3rd Earl of Bute (May 25, 1713-March 10, 1792), was a Scottish nobleman who served as Prime Minister (1762-1763) under George III. He had previously served as tutor to George, who was then the Prince of Wales.

Bute owed his preferment to his friendship with the prince's widowed mother, Augusta of Saxe-Gotha, the Dowager Princess of Wales. It was rumoured that the couple were having an affair, but this was almost certainly untrue, Bute being a deeply religious man and happily married.

Because of the influence he had over his pupil, Bute expected to rise quickly to political power following George's accession to the throne in 1760, but his plans were premature. George began to see through him, and turned against him after being criticised for an official speech which the press recognised as Bute's own work. The journalist John Wilkes published a newspaper called The North Briton, in which both Bute and the Dowager Princess of Wales were savagely satirised. Bute resigned as prime minister shortly afterwards. He remained friendly with the Dowager Princess of Wales, but her attempts to reconcile him with George III proved futile.

{| border="2" align="center" |- |width="30%" align="center"|Preceded by:
James Stuart |width="40%" align="center"|Earl of Bute |width="30%" align="center"|Followed by:
John Stuart |}