| Allendorf | |
| Image Coa: | DEU Allendorf COA.svg |
| Coordinates: | 50.2679°N 7.9993°W |
| Image Plan: | Allendorf in EMS.svg |
| State: | Rheinland-Pfalz |
| District: | Rhein-Lahn-Kreis |
| Verbandsgemeinde: | Aar-Einrich |
| Elevation: | 325 |
| Area: | 3.03 |
| Postal Code: | 56370 |
| Area Code: | 06486 |
| Licence: | EMS, DIZ, GOH |
| Gemeindeschlüssel: | 07 1 41 001 |
| Mayor: | Lars Denninghoff[1] |
| Leader Term: | 2019 - 24 |
| Party: | SPD |
Allendorf (pronounced as /de/) is a municipality in the district of Rhein-Lahn, in Rhineland-Palatinate, in western Germany. It belongs to the association community of Aar-Einrich.