| Lanchy | |
| Commune Status: | Commune |
| Arrondissement: | Saint-Quentin |
| Canton: | Saint-Quentin-1 |
| Insee: | 02402 |
| Postal Code: | 02590 |
| Mayor: | Xavier de Romance[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Pays du Vermandois |
| Coordinates: | 49.8272°N 3.0764°W |
| Elevation M: | 98 |
| Elevation Min M: | 84 |
| Elevation Max M: | 94 |
| Area Km2: | 3.69 |
Lanchy (pronounced as /fr/) is a commune in the Aisne department in Hauts-de-France in northern France.