Sunken Island or Sunken island may refer to:
Lost lands existing or supposedly existing during the past, which have disappeared as a result of natural disasters,
or: a specific geographical place, in the following countries.
Canada Sunken Island/Reef, in Canim Lake (British Columbia) Sunken Island, New Brunswick, Sunken Island, Nova Scotia, three different places named Sunken Island in Ontario: an island, at 44.83° north, 76.17° west a sandbank at 44.13° north, 78.28° west a sandbank at 45.79° north, 82.30° west
New Zealand Motutara, a usually-submerged island that is exposed if the level of Lake Rotomā drops.
United States Sunken Island, Florida Sunken Island, New Hampshire Sunken Island (Otsego Lake), in Otsego Lake (New York) Sunken Island, Vermont Sunken Island, Virginia