| Casumer Bach | |
| Mouth Location: | Hessel |
| Mouth Coordinates: | 52.0495°N 8.2459°W |
| Subdivision Type1: | Country |
| Length: | 7.2km (04.5miles) |
| Pushpin Map: | North Rhine-Westphalia |
| Pushpin Map Size: | 300 |
| Pushpin Map Caption: | North Rhine-Westphalia |
| Pushpin Map Alt: | Relief Map of North Rhine-Westphalia |
Casumer Bach is a river of North Rhine-Westphalia, Germany. It is approximately 7.2 km long and flows directly into the Hessel east of Versmold.