| Saint-Firmin | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason Saint Firmin.svg |
| Arrondissement: | Gap |
| Canton: | Saint-Bonnet-en-Champsaur |
| Insee: | 05142 |
| Postal Code: | 05800 |
| Mayor: | Jean-Michel Cret[1] |
| Term: | 2024 - 2026 |
| Intercommunality: | Champsaur-Valgaudemar |
| Coordinates: | 44.7822°N 6.03°W |
| Elevation M: | 900 |
| Elevation Min M: | 767 |
| Elevation Max M: | 2776 |
| Area Km2: | 22.39 |
Saint-Firmin (pronounced as /fr/; oc|Sant Fermin) is a commune in the Hautes-Alpes department in southeastern France.
Saint-Firmin has an oceanic climate (Köppen climate classification Cfb). The average annual temperature in Saint-Firmin is . The average annual rainfall is with October as the wettest month. The temperatures are highest on average in July, at around, and lowest in January, at around . The highest temperature ever recorded in Saint-Firmin was on 19 August 2012; the coldest temperature ever recorded was on 27 December 1962.