Johann Ernst of Saxony
Johann Ernst von Sachsen is the name of the following people:
- Johann Ernst (Saxe-Coburg) (1521–1553), Duke of Saxe-Coburg
- Johann Ernst (Saxe-Coburg-Saalfeld) (1658–1729), Duke of Saxe-Saalfeld
- Johann Ernst (Saxe-Eisenach) (1566–1638), Duke of Saxe-Eisenach and Duke of Saxe-Coburg
- Johann Ernst I (Saxe-Weimar) ( the younger ; 1594–1626), Duke of Saxe-Weimar
- Johann Ernst II (Saxe-Weimar) (1627–1683), Duke of Saxe-Weimar
- Johann Ernst III. (Saxe-Weimar) (1664–1707), Duke of Saxe-Weimar
- Johann Ernst IV (Saxe-Weimar) (1696–1715), Duke of Saxe-Weimar and composer
