| Lena Delta Nature Reserve | |
| Alt Name: | Russian: Усть-Ленский (государственный природный) заповедник |
| Iucn Category: | Ia |
| Location: | Sakha Republic, Russia |
| Nearest City: | Tiksi |
| Coordinates: | 73.1811°N 125.3158°W |
| Area Km2: | 14330 |
| Established: | 1985 |
Lena Delta Nature Reserve (Russian: Усть-Ленский государственный природный заповедник) is a Zapovednik (“scientific nature reserve”) located in the delta of the Lena River in Sakha Republic, in the far north of eastern Siberia, Russia. The reserve is divided into two subareas, and has a total land area of 14330km2, making it one of the largest protected areas in Russia. The delta itself has a size of about 30000km2, making it one of the largest in the world. It protects large concentrations of birds, including swans, geese and ducks, loons, shorebirds, raptors and gulls. It is also an important fish spawning site.
The Lena's main outlets are the Trofimov (70%), Bykov and Olenek. Nearby is the settlement of Tiksi, the administrative center of Bulunsky District, on the Bykov channel.