| Country: | IRL |
| Type: | R |
| Image Notes: | R677 passing under Kilmacthomas Viaduct |
| Route: | 677 |
| Length Km: | 24.2 |
| Terminus A: | R676 at Carrickbeg, County Waterford |
| Junction: |
|
| Terminus B: | R675 at Seafield |
| Previous Type: | R |
| Previous Route: | 676 |
| Next Type: | R |
| Next Route: | 678 |
The R677 road is a regional road in County Waterford, Ireland. It travels from the R676 road to the R675, via the villages of Kilmacthomas and Ballylaneen. The road is 24.2km (15miles) long.