Prince Keqin of the Second Rank (Manchu: ᡩᠣᡵᠣᡳ
ᠪᠠᡥᠠᠮᡝ
ᡴᡳᠴᡝᠮᠪᡳ
ᡤᡳᠶᡡᠨ
ᠸᠠᠩ; doroi bahame kicembi giyūn wang), or simply Prince Keqin, 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 Yoto (1599–1639), a grandson of Nurhaci, the founder of the Qing dynasty. In 1636, he was awarded the title "Prince Cheng of the First Rank" (Prince Cheng) by his uncle Huangtaiji, who succeeded Nurhaci as the ruler of the Qing Empire. However, he was subsequently demoted for committing offences. After his death, he was posthumously honoured with the title "Prince Keqin of the Second Rank". Yoto's son and successor, Luoluohun (died 1646), inherited the peerage as "Prince Yanxi of the Second Rank" (Prince Yanxi). The peerage was renamed again to "Prince Ping of the Second Rank" (Prince Ping) when it was passed on to Luoluohun's son, Luokeduo (died 1682).
During the reign of the Qianlong Emperor, the peerage was restored to its former name, "Prince Keqin of the Second Rank", and awarded "iron-cap" status. It was passed down over 13 generations and held by 17 persons – one as Prince Cheng, one as Prince Yanxi, six as Prince Ping, and nine as Prince Keqin.