| Ernest | |
| Succession: | Duke of Saxe-Hildburghausen |
| Reign: | 1675–1715 |
| Predecessor: | New creation |
| Successor: | Ernest Frederick I |
| Spouse: | Sophie of Waldeck |
| Issue: | Ernest Frederick I Prince Joseph |
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| Issue-Pipe: | among others... |
| House: | Saxe-Hildburghausen |
| Father: | Ernest I, Duke of Saxe-Gotha |
| Mother: | Elisabeth Sophie of Saxe-Altenburg |
| Birth Date: | 12 June 1655 |
| Birth Place: | Gotha |
| Death Place: | Hildburghausen |
| Religion: | Lutheran |
Ernest, Duke of Saxe-Hildburghausen (12 June 1655 in Gotha – 17 October 1715 in Hildburghausen) was a duke of Saxe-Hildburghausen.
He was the ninth but sixth surviving son of Ernest I, Duke of Saxe-Gotha and Elisabeth Sophie of Saxe-Altenburg.
When his father died in 1675, Ernest and his six brothers jointly assumed the government of the duchy; five years later, in 1680, and under the treaty of division of the family lands, he received the towns of Hildburghausen, Eisfeld, Heldburg, Königsberg. Ernest became thereby founder and first duke of Saxe-Hildburghausen. After the death of his brothers Heinrich and Albrecht without male descendants, he took the towns of Sonnefeld and Behringen.
Ernest settled his official residence in Hildburghausen and began the building of his castle. In 1710 he approved the building in his lands of a new city of French Huguenot families, who were driven out after the Edict of Nantes from France.
As Master of Cavalry he fought in 1683 in the Battle of Vienna, and 1685 in the conquest of Gran and Neuhaeusel, after this he entered the Dutch States Army as a Colonel with the conquest of Kaiserswerth.
In the building of his new residence, Ernest acquired a serious indebtedness of the principality to his brothers, which could not be reduced even by ever larger taxations.
He was married in Arolsen on the 30 November 1680 to Sophie of Waldeck. They had five children: