| Mellionnec | |
| Native Name: | Melioneg |
| Commune Status: | Commune |
| Coordinates: | 48.1756°N -3.2953°W |
| Insee: | 22146 |
| Postal Code: | 22110 |
| Arrondissement: | Guingamp |
| Canton: | Rostrenen |
| Mayor: | Pierre-Yves Daniel[1] |
| Term: | 2024 - 2026 |
| Intercommunality: | Kreiz-Breizh |
| Elevation Min M: | 143 |
| Elevation Max M: | 281 |
| Area Km2: | 24.22 |
Mellionnec (in French pronounced as /mɛljɔnɛk/;) is a commune in the Côtes-d'Armor department in Brittany in northwestern France. The chapel of La Pitié is situated in the commune.
Inhabitants of Mellionnec are called mellionnecais in French.