Great Island is an island within Cork Harbour in Ireland.
Great Island may also refer to: Great Island (Newfoundland and Labrador), an island in Canada Great Island, Falkland Islands "The Great Island" another name for Madagascar Great Island (New Zealand), an island in Fiordland, New Zealand Manawatāwhi / Great Island, an island in the Three Kings Islands group of New Zealand Great Island or King's Island, an island of Enfield, Connecticut Great Island (Massachusetts), an island of Massachusetts Great Island Power Station, County Wexford, Ireland
See also Great Barrier Island, an island off New Zealand