| Marcq | |
| Commune Status: | Commune |
| Arrondissement: | Rambouillet |
| Canton: | Aubergenville |
| Insee: | 78364 |
| Postal Code: | 78770 |
| Mayor: | Magali Mejean-Giron[1] |
| Term: | 2022 - 2026 |
| Coordinates: | 48.8603°N 1.8197°W |
| Elevation Min M: | 117 |
| Elevation Max M: | 172 |
| Area Km2: | 4.72 |
Marcq (in French pronounced as /maʁk/) is a commune in the Yvelines department in the Île-de-France region in north-central France.