National Highways has announced that Network Rail will be carrying out maintenance work on the Onibury Level Crossing.
As a result the A49 will be closed from Craven Arms to Bromfield for two nights, with a diversion put in place.
National Highways said that the closures would take place on Saturday, August 5, and Saturday, August 12.
They will be from 11pm until 9.40am the following day.
The closure will take place from the A49's roundabout junction with the B4368 Clun Road and Dale Street, at Craven Arms, and its junction with the A4113, at Bromfield.
A spokesman for National Highways said: "Vehicles being used for police, fire and rescue authority or ambulance purposes, and vehicles being used in connection with the works will be exempt from the closure.
"Access to properties will be in operation at all times.
"Diversion routes via the B4368, the A442 and the A456 and vice versa will be signed. Local diversions will also be available."