| Lanhouarneau | |
| Native Name: | Lanhouarne |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Lanhouarneau (Finistere).svg |
| Coordinates: | 48.5817°N -4.2089°W |
| Insee: | 29111 |
| Postal Code: | 29430 |
| Arrondissement: | Morlaix |
| Canton: | Saint-Pol-de-Léon |
| Mayor: | Éric Pennec[1] |
| Term: | 2020 - 2026 |
| Elevation Min M: | 17 |
| Elevation Max M: | 106 |
| Area Km2: | 17.69 |
Lanhouarneau is a commune in the Finistère department of Brittany in north-western France.
Inhabitants of Lanhouarneau are called in French Lanhouarnéens.