| Mesquer | |
| Native Name: | (Gallo) |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Mesquer (Loire-Atlantique).svg |
| Arrondissement: | Saint-Nazaire |
| Canton: | Guérande |
| Insee: | 44097 |
| Postal Code: | 44420 |
| Mayor: | Jean-Pierre Bernard[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | CA Presqu'île de Guérande Atlantique |
| Coordinates: | 47.4003°N -2.4586°W |
| Elevation M: | 6 |
| Elevation Min M: | 0 |
| Elevation Max M: | 34 |
| Area Km2: | 16.72 |
Mesquer (in French pronounced as /mɛskɛʁ/; Gallo: Mésqè, Breton: Mesker) is a commune in the Loire-Atlantique department in western France.