Captain John Porteous was a Scottish military officer who served in the Edinburgh City Guard and played a major role in the Porteous Riots, which resulted in his death.

The Porteous Riots surrounded the activities of Captain John Porteous, Captain of the City Guard of Edinburgh, Scotland, who was lynched by a mob for his part in the killing of innocent civilians while ordering the men under his command to quell a disturbance during a public hanging in the Grassmarket, Edinburgh in April 1736. Although the rioters were generally supportive of the convicted smugglers, Porteous seems to have been a somewhat overbearing official, despised by the mob and the underclasses of Edinburgh society.