| Province: | NS |
| Type: | Route |
| Route: | 340 |
| Maint: | Nova Scotia Department of Transportation and Infrastructure Renewal |
| Length Km: | 80 |
| Length Round: | 0 |
| Length Ref: | [1] |
| Direction A: | South |
| Direction B: | North |
| Terminus A: | in Hebron |
| Junction: | in Hebron in Carleton |
| Terminus B: | in Weymouth |
| Counties: | Yarmouth, Digby |
| Previous Type: | Route |
| Previous Route: | 337 |
| Next Type: | Route |
| Next Route: | 341 |
Route 340 is a collector road in the Canadian province of Nova Scotia.
It is located in the western part of the province and connects Hebron at Trunk 1 with Weymouth at Trunk 1.
Before 1970, Route 340 was called Trunk Route 40.