| Saint-Ségal | |
| Native Name: | Sant-Segal |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Saint Segal (Finistère).svg |
| Coordinates: | 48.2417°N -4.0647°W |
| Elevation Min M: | 2 |
| Elevation Max M: | 140 |
| Insee: | 29263 |
| Postal Code: | 29590 |
| Arrondissement: | Châteaulin |
| Canton: | Pont-de-Buis-lès-Quimerch |
| Mayor: | Frederic Drelon[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Pleyben-Châteaulin-Porzay |
| Area Km2: | 16.20 |
Saint-Ségal (in French pronounced as /sɛ̃ seɡal/; Breton: Sant-Segal) is a commune in the Finistère department of Brittany in north-western France.
Saint-Ségal has an oceanic climate (Köppen climate classification Cfb). The average annual temperature in Saint-Ségal is . The average annual rainfall is with January as the wettest month. The temperatures are highest on average in August, at around, and lowest in January, at around . The highest temperature ever recorded in Saint-Ségal was on 3 August 1990; the coldest temperature ever recorded was on 9 February 1991.
Inhabitants of Saint-Ségal are called in French Saint-Ségalais.