| Longchamp-sur-Aujon | |
| Commune Status: | Commune |
| Arrondissement: | Bar-sur-Aube |
| Canton: | Bar-sur-Aube |
| Insee: | 10203 |
| Postal Code: | 10310 |
| Mayor: | Patrick Mary[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Région de Bar-sur-Aube |
| Coordinates: | 48.1508°N 4.8319°W |
| Elevation M: | 192 |
| Elevation Min M: | 192 |
| Elevation Max M: | 334 |
| Area Km2: | 16.39 |
Longchamp-sur-Aujon (pronounced as /fr/, literally Longchamp on Aujon) is a commune in the Aube department in north-central France.
The Aujon forms part of the commune's eastern border, crosses the village, flows west through the middle of the commune, then flows into the Aube, which forms the commune's western border.