Baron Friedrich Karl Gottlob von Varnbüler und zu Hemmingen (13 May 1809 – 26 March 1889) was a Württemberg politician.

His younger sister Ernestine married Count Götz Christoph von Degenfeld-Schonburg, a Württemberg officer and the king's aide-de-camp, in 1831.

[1] As a representative of the knighthood of the Neckarkreis, Varnbüler held a seat in the lower house (German: Abgeordnetenhaus) of the Württemberg State Parliament from 1845 to 1849 and, again, from 1851 until his death in 1889.

After Prussia's victory, King Charles dispatched Prince Frederick and Varnbüler to the Prussian headquarters in Mikulov in June 1866.

On 5 August, Otto von Bismarck demanded the southern German States send appropriately authorized envoys to Berlin for peace negotiations.

On 23 March 1870, the King appointed the Foreign Minister as President of the Privy Council, succeeding Ludwig von Golther.

A few weeks after the outbreak of the Franco-Prussian War, he retired on 31 August 1870 and was succeeded by Hermann von Mittnacht as senior minister.