| Düpenau | |
| Mouth Location: | Mühlenau |
| Mouth Coordinates: | 53.6473°N 9.8285°W |
| Progression: | Mühlenau→ |
| Subdivision Type1: | Country |
| Subdivision Name1: | Germany |
| Subdivision Type2: | States |
| Subdivision Name2: | Hamburg and Schleswig-Holstein |
Düpenau is a river of Hamburg and Schleswig-Holstein, Germany. In Osdorf, Hamburg it flows through Lake Helmuth Schack. It is a tributary of the Mühlenau near Pinneberg.