| Saint-Mars-la-Brière | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Saint-Mars-la-Brière (Sarthe).svg |
| Arrondissement: | Mamers |
| Canton: | Savigné-l'Évêque |
| Insee: | 72300 |
| Postal Code: | 72470 |
| Mayor: | Patrice Vernhettes[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Le Gesnois Bilurien |
| Coordinates: | 48.0294°N 0.3716°W |
| Area Km2: | 34.69 |
| Demonym: | Brierois, Brieroise |
Saint-Mars-la-Brière (in French pronounced as /sɛ̃ maʁ la bʁijɛʁ/) is a commune in the Sarthe department in the region of Pays de la Loire in north-western France.