Yamdena (spelled Jamdena during the Dutch colonial period) is the largest of the Tanimbar Islands in the Maluku province of Indonesia.

Saumlaki is the chief town, located on the south end of the island.

[1] Christianity is the main religion, but ancestor worship is still practised.

[2] Megalith: In the village of Sangliat Dol there is an antique stone stairway that leads from the beach to a boat shaped stone platform.

Saumlaki is linked by air and sea to Langgur-Tual in the Kei Islands.