| Château-Gontier-sur-Mayenne | |
| Commune Status: | Subprefecture and commune |
| Arrondissement: | Château-Gontier |
| Canton: | Château-Gontier-sur-Mayenne-1 and 2 |
| Mayor: | Philippe Henry[1] |
| Term: | 2020 - 2026 |
| Coordinates: | 47.8286°N -0.7028°W |
| Elevation Min M: | 22 |
| Elevation Max M: | 99 |
| Area Km2: | 68.49 |
| Insee: | 53062 |
| Postal Code: | 53200 |
Château-Gontier-sur-Mayenne (pronounced as /fr/) is a commune in the Mayenne department in north-western France.[2] It was established on 1 January 2019 by merger of the former communes of Château-Gontier (the seat), Azé and Saint-Fort.[3]