The Department of Infrastructure says the Mountain Road will close next month, marking the end of the roadracing season.
The route is due to shut on September 2 and 3 as equipment needed for racing is removed between Ramsey and the Bungalow.
There'll then be a second closure between the Bungalow and CregNyBaa on September 9 and 10.
The road will close from 9.30am to 8pm on both days.