The A31 road between Boundary Lane and Ashley Heath will be closed every night from 2100 – 0600 till the end of November.
Eastbound traffic will be diverted via Ferndown, West Parley, Hurn and the A338, whilst westbound traffic will be down to a single lane.
The closures are due to work being carried out on the lighting at the Woolsbridge roundabout – where Travelodge and Avon Heath Country Park are.