The L2104 near Caherlistrane will be closed for the next three days to allow for the construction of an underpass.
The road will be closed from junction of the N84 and L2104 at Carrowmore to the junction of the L2104 and R333 at Oltore.
The road will be closed from 8am on Monday, May 6 to 8pm on Wednesday, May 8.
Galway county council has ordered the road closure to allow for the construction of a cattle underpass.
Motorists travelling in the area can follow a suggested diversion along the R333 where it meets the N84 just north of Headford.