| Ilz | |
| Map: | Ilz, rivière de Bavière.png |
| Source1 Location: | Bavarian Forest |
| Mouth Location: | Danube |
| Mouth Coordinates: | 48.5753°N 13.4756°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Germany |
| Subdivision Type2: | State |
| Subdivision Name2: | Bavaria |
| Length: | 40.3km (25miles) |
| Source1 Elevation: | ±430m (1,410feet) |
| Basin Size: | 850km2 |
The Ilz (pronounced as /de/) is a river running through the Bavarian Forest, Germany. It is a left tributary of the Danube. During its length (including its main source river Große Ohe), it travels down a height difference of ~140m.
The Ilz is formed at the confluence of its source rivers Große Ohe and Kleine Ohe in Eberhardsreuth. In the city of Passau it finally enters the Danube. Another town on the Ilz is Fürsteneck.