| Karl Friedrich | |
| Prince of Hohenzollern-Sigmaringen | |
| Reign: | 1769–1785 |
| Issue: | Anton Aloys Johanna Franziska, Princess of Salm-Kyburg Maria Kreszentia, Lady of Holzen and Countess of Treuberg. |
| Mother: | Maria Franziska of Oettingen-Spielberg |
| Birth Date: | 9 January 1724 |
| Death Place: | Krauchenwies |
Karl Friedrich (9 January 1724 – 20 December 1785) was a member of the House of Hohenzollern and Prince of Hohenzollern-Sigmaringen, Lord of Haigerloch and Wehrstein from 1769 until his death.
Born in Sigmaringen, he was the eldest son of Joseph Friedrich Ernst, Prince of Hohenzollern-Sigmaringen and his first wife, Maria Franziska Louise of Oettingen-Spielberg. From the nine children that his father produced in his first and second marriage, only Karl Friedrich and a young full-sister, Maria Johanna (who became a nun) survived to adulthood.
Karl Friedrich was first educated in Sigmaringen and Munich. Later, he went to the Universities of Freiburg, Göttingen and Ingolstadt. He returned to Sigmaringen in 1746 and soon parted on the customary Grand Tour (a kind of educational trip) through Germany, Austria and Italy.
During his stay in the Netherlands visiting relatives, he met his future wife. On 2 March 1749 at the Kail Castle, Karl Friedrich married with his first-cousin Johanna Josephina Antonia (14 April 1727 – 22 February 1787), a daughter of Count Franz Wilhelm of Hohenzollern-Berg. The wedding took place not only for political reasons, but Karl Friedrich had a deep affection for his bride. Johanna was the heiress of the rich Dutch County of Bergh-'s-Heerenberg, and for this they spent more time in their Dutch states than in the Principality of Sigmaringen.
Karl Friedrich sided with Empress Maria Theresa of Austria against Prussia during the Seven Years' War. Until 1763 he served in the cavalry regiment as part of the troops of the Swabian Empire Circle. During the conflict, he mostly fought against Friedrich Wilhelm von Seydlitz, leader of the Prussian cavalry.
In the Principality of Sigmaringen the military conflict had virtually no repercussions, a fact which favored the development of the local economy. Karl Friedrich was Erbkämmerer of the Holy Roman Empire and Field Marshal Lieutenant (Feldmarschall-Leutnant) of the Swabian Empire Circle. Despite his military activities, he was very enthusiastic for hunting.