William the Good | |
|---|---|
| Count of Hainaut, Holland, and Zeeland | |
 16th-century depiction | |
| Born | c. 1286 |
| Died | 7 June 1337 Valenciennes |
| Noble family | House of Avesnes |
| Spouse(s) | Joan of Valois |
| Issue | William II, Count of Hainaut Margaret II, Countess of Hainaut Philippa, Queen of England Joanna, Duchess of Jülich Isabella of Hainaut |
| Father | John II, Count of Hainaut |
| Mother | Philippa of Luxembourg |
William the Good (Dutch: Willem, French: Guillaume; c. 1286 – 7 June 1337) was count of Hainaut (as William I), Avesnes, Holland (as William III), and Zeeland (as William II) from 1304 to his death.