| Nienhagen | |
| Image Coa: | Wappen Nienhagen (Landkreis Celle).png |
| Coordinates: | 52.55°N 16°W |
| Image Plan: | Nienhagen in CE.svg |
| State: | Niedersachsen |
| District: | Celle |
| Samtgemeinde: | Wathlingen |
| Elevation: | 41 |
| Area: | 17.57 |
| Postal Code: | 29336 |
| Area Code: | 05144 |
| Licence: | CE |
| Gemeindeschlüssel: | 03 3 51 018 |
| Divisions: | 3 Ortsteile |
| Website: | www.nienhagen.de |
| Mayor: | Jörg Makel |
| Party: | SPD |
Nienhagen is a municipality in the district of Celle, in Lower Saxony, Germany.