Feng'en zhenguo gong (Chinese: 奉恩鎮國公; pinyin: Fèng'ēn zhènguó gōng; Manchu: ᡴᡝᠰᡳ ᠪᡝ ᡨᡠ᠋ᠸᠠᡴᡳᠶᠠᡵᠠ ᡤᡠᡵᡠᠨ ᠪᡝ ᡩᠠᠯᡳᡵᡝ ᡤᡠᠩ, Möllendorff: kesi-be tuwakiyara gurun-be dalire gung; Mongolian: Хишгийг сахих улсын түшээ гүн), translated as "Grace Defender Duke" or "Duke Who Guards the State by the Grace" or "State Duke of the First Rank", was one of the royal and noble titles of the Qing dynasty.
The son of Primary Princess Consort of the First Rank could be further promoted until he reached the father's title (iron-cap peerage).
[5] Princess consort was styled as "feng'en zhenguo gong furen" (奉恩鎮國公夫人), which translates to "State Duchess of the First Rank".
[6] Daughter born to primary consort of feng'en zhenguo duke was granted a title of Lady of the Third Rank (鄉君).
Daughters born to secondary consort of feng'en zhenguo gong was granted a title of sixth rank clanswoman.