Mannar is the main town of Mannar District, Northern Province, Sri Lanka. It is governed by an Urban Council. The town is located on Mannar Island overlooking the Gulf of Mannar and is home to the historic Ketheeswaram temple. In the Tamil language, Mannar means the raised place [of sand] which is thought to have come from the geology of Mannar Island which was formed by the accumulation of sand.

Mannar District is one of the 25 districts of Sri Lanka, the second level administrative division of the country. The district is administered by a District Secretariat headed by a District Secretary appointed by the central government of Sri Lanka. The capital of the district is Mannar, which is located on Mannar Island.