Princess Sophie of Saxe-Hildburghausen (Ernestine Friederike Sophie; 22 February 1760, Hildburghausen – 28 October 1776, Coburg), was a Princess of Saxe-Hildburghausen by birth, and by marriage she became the Hereditary Princess of Saxe-Coburg-Saalfeld.

Ernestine Friederike Sophie was the daughter of Duke Ernest Frederick III of Saxe-Hildburghausen (1727–1780) and Princess Ernestine of Saxe-Weimar (1740–1786). Her godparents were the Danish royal couple, the King of Poland, and the Regents of the houses of Saxe-Coburg, Saxe-Weimar, Mecklenburg and Württemberg.

On 6 March 1776, she married at the age of 16 (in Hildburghausen) the Hereditary Prince (and later Duke) Francis Frederick Anthony of Saxe-Coburg-Saalfeld. At the time, Francis was already in love with his future wife Countess Augusta Reuss of Ebersdorf, but he was unable to break off his engagement with Sophie.

Sophie died of influenza just six months later, on 28 October 1776. She remained childless. She was buried in the crypt of the St. Moritz Church in Coburg.

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