The R165 road is a regional road in Ireland, linking the R188 5 km (3.1 mi) west of Cootehill in County Cavan to the N2 near Ardee, County Louth.
The route is 64 km (40 mi) long.
Northeast to southwest, the route starts at a junction with the R188 west of Cootehill. It continues southwards through Stradone, to join the N3 and in 500 m leaves the N3 at Lavey.
It heads southeast through Bailieborough and Kingscourt, crosses the N52 then enters County Louth and terminates at the N2 3 km (1.9 mi) south of Ardee.