| Type: | Ortsgemeinde |
| Image Coa: | DEU Onsdorf COA.svg |
| Coordinates: | 49.6442°N 6.4824°W |
| Image Plan: | Onsdorf in TR.svg |
| State: | Rheinland-Pfalz |
| District: | Trier-Saarburg |
| Verbandsgemeinde: | Konz |
| Elevation: | 295 |
| Area: | 3.42 |
| Postal Code: | 54456 |
| Area Code: | 06584 |
| Licence: | TR |
| Gemeindeschlüssel: | 07 2 35 101 |
| Mayor: | Klaus Fuchs[1] |
| Leader Term: | 2019 - 24 |
| Party: | SPD |
Onsdorf is a municipality in the Trier-Saarburg district, in Rhineland-Palatinate, Germany.
From 18 July 1946 to 6 June 1947 Onsdorf, in its then municipal boundary, formed part of the Saar Protectorate.