The Mantanani Islands form a small group of three islands off the north-west coast of the state of Sabah, Malaysia, opposite the town of Kota Belud, in northern Borneo. The largest island is Mantanani Besar; the other two are Mantanani Kecil and Lungisan. It is a popular site for recreational diving as there are three nearby dive wrecks dating from the Second World War, as well as being known for its dugongs.