William of Berg may refer to:
William I of Berg ( 1242–1308), son of Count Adolf VII of Berg and Margaret of Hochstaden William IV, Duke of Jülich-Berg (1455–1511), last ruler of the Duchy of Jülich-Berg William, Duke of Jülich-Cleves-Berg (1516–1592) William VII of Jülich, 1st Duke of Berg (1348–1408), son of Gerhard VI of Jülich, Count of Berg William IV of Berg-s'Heerenberg (1537–1586), Stadtholder of Guelders and Zutphen
See also William Berg (disambiguation)