| Longemaison | |
| Commune Status: | Commune |
| Coordinates: | 47.0822°N 6.46°W |
| Insee: | 25343 |
| Postal Code: | 25690 |
| Arrondissement: | Pontarlier |
| Canton: | Valdahon |
| Mayor: | Claude Brisebard[1] |
| Term: | 2020 - 2026 |
| Elevation Min M: | 730 |
| Elevation Max M: | 1091 |
| Area Km2: | 9.63 |
Longemaison (in French pronounced as /lɔ̃ʒmɛzɔ̃/) is a commune in the Doubs département in the Bourgogne-Franche-Comté region in eastern France.
The village likes on the wooded slopes of the Mont Chaumont, which is the highest point of the commune at 1092 meters.