Moritz Wilhelm, Duke of Saxe-Zeitz (12 March 1664 – 15 November 1718) was a duke of Saxe-Zeitz and member of the House of Wettin.He was born at Moritzburg Castle in Zeitz, the eldest son of Maurice, Duke of Saxe-Zeitz, and his second wife, Dorothea Maria, a daughter of Wilhelm, Duke of Saxe-Weimar. His father had two sons from his first marriage, but both died in infancy long before his birth.