Ashūradeh (Persian: آشوراده), or Ashur Ada, besides Esmaeilsay and Akaz islands, is one of the islands off the Iranian coast on the Caspian Sea (Gorgan Bay).

It is located on the eastern end of the Miankaleh peninsula in the county of Behshahr of Māzandarān Province of Iran, 3 kilometers (1.9 mi) from Bandar Torkaman and 23 kilometers (14 mi) from Gorgan.

Over 40% of Iran's caviar is produced near Ashūradeh Island.

The island was occupied by Russian forces in 1837, despite protests from Persia.

[4] Following the occupation, the Russian Army maintained a military post on the island for a few decades until 1921.