Frederick Bernard, Count Palatine of Gelnhausen (28 May 1697 in Gelnhausen – 5 August 1739, ibid.) was Count Palatine and Duke of Birkenfeld-Gelnhausen.
Frederick Bernard was the eldest son of the Duke and Count Palatine John Charles of Gelnhausen (1638-1704) from his second marriage to Esther Maria (1665-1725), the daughter of Baron George Frederick of Witzleben-Elgersburg.
In 1704, he succeeded his father as Count Palatine of Birkenfeld-Gelnhausen. He served in the French army as a colonel of the Royal Alsatian regiment. He was a knight of the Order of Saint Hubert. A treaty of 1736 with Caroline, the regent of Zweibrücken, granted Frederick Bernard an annual allowance of .
Frederick Bernard died in 1739 without a male heir. Gelnhause was inherited by his younger brother John.
Frederick Bernard married on 30 May 1737 in Arolsen to Princess Ernestine Louise of Waldeck-Pyrmont (1705-1782), the daughter of Friedrich Anton Ulrich, Prince of Waldeck and Pyrmont. Her mother was Frederick Bernard's cousin, Countess palatine Louise of Palatinate-Birkenfeld-Bischweiler. Frederick Bernard and Ernestine Louise had two daughters: