Isdhoo or Isdū (according to the Admiralty charts) (Dhivehi: އިސްދޫ) is one of the inhabited islands of Haddhunmathi Atoll, administrative code Laamu part of Maldives in the Indian Ocean.

[3] The oldest lōmāfānu that have hitherto been found and preserved are from Malé, the royal capital, and from the islands of Isdū and Dambidū in Haddhunmathi Atoll, where there were large Buddhist monasteries.

[3] These (lōmāfānu), make it clear that the general conversion from Buddhism to Islam was ordered by the king.

Thanks to the lōmāfānu it is also known that the monasteries in Haddummati Atoll (Satu Duvu) were of great importance in the ancient Buddhist Kingdom of the Maldives.

According to the Isdū Lōmāfānu, monks from monasteries of the southern atoll of Haddhunmathi were brought to Malé and beheaded.