John was the younger son of the Duke and Count Palatine John Charles of Birkenfeld-Gelnhausen (1638-1704) from his second marriage with Esther Maria (1665–1725), a daughter of Baron George Frederick of Witzleben-Elgersburg.

After the death of his brother Frederick Bernard in 1739, he succeeded as Count Palatine of Birkenfeld-Gelnhausen.

Johann married in 1743 in Dhaun with Sophie Charlotte (1719–1770), a daughter of the Wild- and Rhinegrave Charles of Salm-Dhaun.

Sophie Charlotte was the granddaughter of two of Johann's first cousins, making the couple first cousins twice removed in descent from Christian I, Count Palatine of Birkenfeld-Bischweiler.

This article about a member of the German nobility is a stub.