Adonara is an island in the Lesser Sunda Islands of Indonesia, located east of the larger island of Flores in the Solor Archipelago. To the east lies Lembata, formerly known as Lomblen. It is the highest of the islands of the archipelago, reaching an altitude of 1,659 metres, and it has an area of 497 km². It is in the East Nusa Tenggara province.
Adonara Island is a part of the Indonesian regency of East Flores. It can be reached by airplane from Jakarta to Kupang, then by ferry to Larantuka, then by boat. The administrative centre of Adonara is the town of Waiwerang.