William of Holland
William of Holland may refer to:
- William I, Count of Holland, Count of Holland from 1203 to 1222
- William II, Count of Holland, count of Holland and Zeeland, elected German anti-king in 1247
- William III, Count of Holland, Count William III of Avesnes and of Holland and Count William II of Zeeland
- William IV, Count of Holland was William IV of Avesnes, William IV of Holland and William III of Zeeland
- William V, Count of Holland,, known as William V, Count of Holland, William III, Count of Hainault, William I, Duke of Bavaria-Straubing and William IV, Count of Zeeland
- William VI, Count of Holland,, also known as William II of Bavaria-Straubing, count William IV of Hainaut and count William V of Zeeland