| Lanhélin | |
| Native Name: | Lanhelen |
| Coordinates: | 48.4594°N -1.8269°W |
| Insee: | 35147 |
| Postal Code: | 35720 |
| Arrondissement: | Saint-Malo |
| Canton: | Combourg |
| Commune: | Mesnil-Roc'h |
| Elevation Min M: | 44 |
| Elevation Max M: | 88 |
| Area Km2: | 6.43 |
| Population: | 946 |
| Population Date: | 2019 |
| Population Footnotes: | [1] |
Lanhélin (pronounced as /fr/; br|Lanhelen) is a former commune in the Ille-et-Vilaine department in Brittany in northwestern France. On 1 January 2019, it was merged into the new commune Mesnil-Roc'h.[2]
The inhabitants of Lanhélin are known as Lanhélinois in French.