| Grébault-Mesnil | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason Grébault-Mesnil.svg |
| Arrondissement: | Abbeville |
| Canton: | Abbeville-2 |
| Insee: | 80388 |
| Postal Code: | 80140 |
| Mayor: | Julien Lefebvre[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | CC Vimeu |
| Coordinates: | 50.0261°N 1.7214°W |
| Elevation M: | 94 |
| Elevation Min M: | 93 |
| Elevation Max M: | 113 |
| Area Km2: | 2.58 |
Grébault-Mesnil (in French pronounced as /ɡʁebo menil/; Guérbeu-Mégni) is a commune in the Somme department in Hauts-de-France in northern France.
The commune is situated on the D86 road, some 8 miles (12 km) southwest of Abbeville.