| Coordinates: | 52.8833°N 71°W |
| Image Plan: | Rüthnick in OPR.png |
| State: | Brandenburg |
| District: | Ostprignitz-Ruppin |
| Amt: | Lindow (Mark) |
| Elevation: | 40 |
| Area: | 17.66 |
| Postal Code: | 16835 |
| Area Code: | 033926 |
| Licence: | OPR |
| Gemeindeschlüssel: | 12 0 68 372 |
| Mayor: | Birgit Salzwedel[1] |
| Leader Term: | 2024 - 29 |
Rüthnick is a municipality in the Ostprignitz-Ruppin district, in Brandenburg, Germany.