The R684 road is a regional road in Ireland. Located in the south of Ireland near Waterford City, it links the junction with the R683 at Blenheim Cross to the village of Dunmore East in County Waterford.
It runs via Callaghane Bridge, Kilmacomb, where it meets the R685, and terminates at Dock Road in Dunmore East.
In addition to the section of the R683 linking Waterford city to the junction at Blenheim Cross, the R684 is known as the Dunmore Rd.