Duke Henry IV of Mecklenburg (c. 1340–1383) was a notable nobleman from the House of Mecklenburg, a prominent dynasty in northern Germany. He ruled the duchy of Mecklenburg alongside his brother, Duke Albert III, after their father's death. His reign was marked by efforts to strengthen the duchy's political and economic stability. Henry IV is remembered for his involvement in regional conflicts and alliances, particularly with the Hanseatic League, a powerful trading alliance in the Baltic Sea. His leadership contributed to the development of Mecklenburg as a significant player in the politics of northern Europe during the late 14th century.