Johann Georg, Duke of Saxe-Weissenfels (13 July 1677, in Halle – 16 March 1712, in Weissenfels), was a duke of Saxe-Weissenfels-Querfurt and a member of the House of Wettin.
He was the third child and first surviving son of Johann Adolf I, Duke of Saxe-Weissenfels, by his first wife, Johanna Magdalena of Saxe-Altenburg.