Johann Adolf I, Duke of Saxe-Weissenfels (2 November 1649, in Halle – 24 May 1697, in Weissenfels), was a duke of Saxe-Weissenfels-Querfurt and member of the House of Wettin.
He was the first son of Augustus, Duke of Saxe-Weissenfels, and his first wife, Anna Maria of Mecklenburg-Schwerin.