A three-kilometre stretch of road between Wickepin and Kulin will be widened to bring it in line with modern safety standards.
Currently, vehicles travelling along the Narrogin-Kondinin road have to veer onto the gravel when approaching oncoming traffic.
The $1.25 million project will involve widening the road to two lanes.
Transport Minister Simon O’Brien says the work will improve safety on what is an important regional route.
The works are scheduled to begin this month and are expected to be completed in May.