Prince Su of the First Rank (Manchu: ᡩᠣᡵᠣᠨᡶᠠᡶᡠᠩᡤᡠᠴᡳᠨ ᠸᠠᠩ; hošoi fafunggu cin wang), or simply Prince Su, was the title of a princely peerage used in China during the Manchu-led Qing dynasty (1644–1912). It was also one of the 12 "iron-cap" princely peerages in the Qing dynasty, which meant that the title could be passed down without being downgraded. The first bearer of the title was Hooge (1609–1648), the eldest son of Huangtaiji, the second ruler of the Qing dynasty. He was awarded the title in 1636 by his father. The peerage was renamed to Prince Xian of the First Rank (Prince Xian) when it was passed on to Hooge's son, Fushou (died 1669), in 1651. It was also given "iron-cap" status later on. In 1778, when Yunzhu (died 1778) was holding the title, the Qianlong Emperor renamed it back to "Prince Su of the First Rank". The peerage was passed down over ten generations and held by 11 persons – eight as Prince Su, and three as Prince Xian.