Friedrich Karl Theodor Zarncke (7 July 1825 – 15 October 1891), German philologist, was born at Zahrensdorf, Mecklenburg-Schwerin, the son of a country pastor.
He was educated at the Rostock gymnasium, and studied (1844–1847) at the universities of Rostock, Leipzig and Berlin.
In 1848 he was employed in arranging the valuable library of Old German literature of Freiherr Karl Hartwig von Meusebach (1781–1847), and superintending its removal from Baumgartenbrück, near Potsdam, to the Royal Library at Berlin.In 1850 he founded the Literarisches Centralblatt für Deutschland in Leipzig.
In 1852 he established himself as privatdozent at the university of Leipzig.