| Locarn | |
| Native Name: | Lokarn |
| Commune Status: | Commune |
| Image Coat Of Arms: | COA fr Locarn (Côtes-d'Armor).svg |
| Coordinates: | 48.3206°N -3.4208°W |
| Insee: | 22128 |
| Postal Code: | 22340 |
| Arrondissement: | Guingamp |
| Canton: | Rostrenen |
| Mayor: | Marjorie Bert[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Kreiz-Breizh |
| Elevation Min M: | 92 |
| Elevation Max M: | 282 |
| Area Km2: | 32.36 |
Locarn (in French pronounced as /lɔkaʁn/;) is a commune in the Côtes-d'Armor department of Brittany in northwestern France.
Inhabitants of Locarn are called locarnois or locarnais in French.