| Diogo | |
|---|---|
 Duke of Viseu | |
 Diogo, Duke of Viseu | |
| Duke of Viseu and Beja | |
| Reign | 1472 - 1484 |
| Predecessor | João, Duke of Viseu |
| Successor | Manuel I of Portugal |
| Born | 1450 |
| Died | 1484 |
| House | Aviz |
| Father | Ferdinand, Duke of Viseu |
| Mother | Beatriz of Portugal |
Infante Diogo of Viseu (1450–1484) was the second son of Ferdinand, Duke of Viseu, and his wife Beatriz, Duchess of Viseu.