| Montjay | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason Montjay.svg |
| Arrondissement: | Gap |
| Canton: | Serres |
| Insee: | 05086 |
| Postal Code: | 05150 |
| Mayor: | Gilles Mostachetti[1] |
| Term: | 2020 - 2026 |
| Coordinates: | 44.3608°N 5.6044°W |
| Elevation M: | 814 |
| Elevation Min M: | 764 |
| Elevation Max M: | 1298 |
| Area Km2: | 27 |
Montjay (in French pronounced as /mɔ̃ʒɛ/) is a commune in the Hautes-Alpes department in southeastern France.