| Image Coa: | DEU Nonnweiler COA.svg |
| Coordinates: | 49.6167°N 63°W |
| Image Plan: | Nonnweiler in WND.svg |
| State: | Saarland |
| District: | Sankt Wendel |
| Elevation: | 414 |
| Area: | 66.71 |
| Postal Code: | 66616–66620 |
| Area Code: | 06873 |
| Licence: | WND |
| Gemeindeschlüssel: | 10 0 46 115 |
| Divisions: | 8 |
| Website: | www.nonnweiler.de |
| Mayor: | Franz-Josef Barth[1] |
| Leader Term: | 2019 - 29 |
| Party: | SPD |
Nonnweiler is a municipality in the district of Sankt Wendel, in Saarland, Germany.
It is situated approximately 20 km northwest of Sankt Wendel, and 30 km southeast of Trier. The village is well known for the "Hillfort of Otzenhausen", a huge wall (former castle) of Celtic origin.