| Saint-Séglin | |
| Native Name: | (Gallo) |
| Commune Status: | Commune |
| Coordinates: | 47.8542°N -2.0033°W |
| Insee: | 35311 |
| Postal Code: | 35330 |
| Arrondissement: | Redon |
| Canton: | Guichen |
| Mayor: | Marie Monvoisin[1] |
| Term: | 2020 - 2026 |
| Elevation Min M: | 12 |
| Elevation Max M: | 74 |
| Area Km2: | 9.40 |
Saint-Séglin (in French pronounced as /sɛ̃ seɡlɛ̃/; Breton: Sant-Sewenn; Gallo: Saent-Segelein) is a commune in the Ille-et-Vilaine department in Brittany in northwestern France.
Inhabitants of Saint-Séglin are called Séglinois in French.