Prince Yu of the Second Rank, or simply Prince Yu, was the title of a princely peerage used in China during the Manchu-led Qing dynasty (1644–1912). As the Prince Yu 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.
The first bearer of the title was Yunxu (允禑; 1693–1731), the 15th son of the Kangxi Emperor. In 1730, Yunxu was granted the title "Prince Yu of the Second Rank" by the Qianlong Emperor. The title was passed down over seven generations and held by seven persons.
Members of the Prince Yu peerage
Yunxu (允禑; 1693 – 1731; 1st), the Kangxi Emperor's 15th son, initially a beile, promoted to second-rank prince under the title "Prince Yu of the Second Rank" in 1730, posthumously honoured as Prince Yu Ke of the Second Rank (愉恪郡王)
Hongqing (弘慶; 1724 – 1769; 2nd), Yunxu's third son, held the title Prince Yu of the Second Rank from 1731 to 1769, posthumously honoured as Prince Yu Gong of the Second Rank (愉恭郡王)
Yongjian (永珔; 1766 – 1820; 3rd), Hongqing's eldest son, held the title of a beile from 1770 to 1820
Mianxiu (綿岫; 1782 – 1850; 4th), Yongjian's eldest son, made a defender general in 1802, held the title of a beizi from 1821 to 1850
Zailin (載霖), Yicheng's eldest son, held the title of a supporter general from 1868 to 1889, had no male heir
Zaiguang (載光), Yicheng's fourth son, held the title of a supporter general from 1877
Pupei (溥培), Zaiguang's eldest son, held the title of a grace general from 1906
Zaiyan (載燕), Yicheng's sixth son, held the title of a supporter general from 1877 to 1911
Puping (溥坪), Zaiyan's eldest son, held the title of a grace general from 1906
Yiqiu (奕楸), Mianxiu's fourth son, held the title of a second class bulwark general from 1857 to 1864, had no male heir
Yigen (奕根), Mianxiu's sixth son, held the title of a grace general from 1857 to 1861, had no male heir
Yi'nan (奕楠), Mianxiu's eighth son, held the title of a grace general from 1868 to 1884
Zaizhuang (載莊), Yi'nan's second son and Yilei's adopted son, held the title of a grace general (as Yi'nan's line) from 1890 and another grace general title (as Yilei's heir) from 1902
Yilei (奕櫑), Mianxiu's ninth son, held the title of a grace general from 1868 to 1870, had no male heir
Yisu's cadet line
Zaixiu (載烋), Yisu's eldest son, held the title of a first class bulwark duke from 1857 to 1859, had no male heir