Hedwig of Mecklenburg-Güstrow (Hedwig Eleonore; 12 January 1666 – 9 August 1735), was a German noblewoman member of the House of Mecklenburg and by marriage Duchess of Saxe-Merseburg-Zörbig.
Born in Güstrow, she was the eighth of eleven children born from the marriage of Gustav Adolph, Duke of Mecklenburg-Güstrow and Magdalene Sibylle of Holstein-Gottorp.
From her ten older and younger siblings, eight survive adulthood: Marie (by marriage Duchess of Mecklenburg-Strelitz), Magdalene, Sophie (by marriage Duchess of Württemberg-Oels), Christine (by marriage Countess of Stolberg-Gedern), Charles, Hereditary Prince of Mecklenburg-Güstrow, Louise (by marriage Queen of Denmark and Norway), Elisabeth (by marriage Duchess of Saxe-Merseburg-Spremberg) and Augusta.