Prince Dun of the First Rank, or simply Prince Dun, was the title of a princely peerage used in China during the Manchu-led Qing dynasty (1644–1912). As the Prince Dun peerage was not awarded "iron-cap" status, this meant that each successive bearer of the title would normally start off with a title downgraded by one rank vis-à-vis that held by his predecessor. However, the title would generally not be downgraded to any lower than a feng'en fuguo gong except under special circumstances.