The proposed Northern Road Connectivity Project will cover repairs to about 120 km of national highways in the northern and north-central provinces and about 141 km of provincial roads in the north.
It also includes building or repairing bridges in the two provinces.
The ADB will lend about 130 million dollars for the project, the biggest in the bank’s aid pipeline for the island this year.
Roads in northern Sri Lanka were badly damaged or neglected because of the island’s 30-year ethnic war which ended in May 2009 when government forces defeated Tamil Tiger separatists.
The ADB said in a statement procurement to be financed under the project will be carried out in accordance with ADB's procurement guidelines.
The bank has said it is refocusing its aid to Sri Lanka to cover rebuilding of the north and east where infrastructure was destroyed or neglected because of the war which was fought mainly in those areas.