| Long Danau | |
| Coordinates: | 3.5667°N 115.5°W |
| Pushpin Map: | Borneo |
| Pushpin Label Position: | right |
| Subdivision Type: | Country |
| Subdivision Name: |  Malaysia |
| Subdivision Type1: | State |
| Subdivision Type2: | Administrative Division |
| Subdivision Name2: | Marudi |
| Elevation M: | 961 |
Long Danau is a longhouse settlement in the Marudi division of Sarawak, Malaysia. It lies approximately 615.3km (382.3miles) east-north-east of the state capital Kuching.
The longhouse is about three hours' trek from Ramadu Long Danau has a good reputation with travellers, with good food and a chief who speaks English.
The Bornean Horseshoe Bat (Rhinolophus borneensis) has been observed in Long Danau.
Neighbouring settlements include: