| Saint-Sernin-lès-Lavaur | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Saint-Sernin-lès-Lavaur (Tarn).svg |
| Arrondissement: | Castres |
| Canton: | Le Pastel |
| Insee: | 81270 |
| Postal Code: | 81700 |
| Mayor: | Patrice Biezus[1] |
| Term: | 2020 - 2026 |
| Coordinates: | 43.5489°N 1.9747°W |
| Elevation M: | 210 |
| Elevation Min M: | 187 |
| Elevation Max M: | 275 |
| Area Km2: | 4.21 |
Saint-Sernin-lès-Lavaur (in French pronounced as /sɛ̃ sɛʁnɛ̃ lɛ lavɔʁ/; Occitan (post 1500);: Sant Sarnin de la Vaur) is a commune in the Tarn department in southern France.