| Province: | QC |
| Type: | QC |
| Route: | 251 |
| Maint: | Transports Québec |
| Map: | Route 251-QC.png |
| Length Km: | 38.5 |
| Length Round: | 1 |
| Length Ref: | [1] |
| Direction A: | South |
| Direction B: | North |
| Terminus A: | in Saint-Herménégilde |
| Terminus B: | in Cookshire-Eaton |
| Previous Type: | QC |
| Previous Route: | 249 |
| Next Type: | QC |
| Next Route: | 253 |
| Cities: | Martinville |
| Junction: | in Sainte-Edwidge-de-Clifton in Martinville |
Route 251 is a north–south highway on the south shore of the St. Lawrence River. Its northern terminus is at Route 108 in Cookshire-Eaton, and its southern terminus is at Route 141, in Saint-Herménégilde.