| Mareil-le-Guyon | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Mareil-le-Guyon (Yvelines).svg |
| Arrondissement: | Rambouillet |
| Canton: | Aubergenville |
| Insee: | 78366 |
| Postal Code: | 78490 |
| Mayor: | Michel Lommis[1] |
| Term: | 2020 - 2026 |
| Coordinates: | 48.7911°N 1.8536°W |
| Elevation M: | 73 |
| Elevation Min M: | 67 |
| Elevation Max M: | 112 |
| Area Km2: | 4.00 |
Mareil-le-Guyon (pronounced as /fr/) is a commune in the Yvelines department in the Île-de-France region in north-central France.