Double Island may refer to: Double Island, Queensland, near Cairns, Queensland, Australia Double Island (Shark Bay) in Western Australia Mayu Island and Dezhou Island in Shantou, China, known as Double Island in 19th-century English-language sources Double Island, Hong Kong, in northeastern New Territories, Hong Kong Double Island (Washington), one of the San Juan Islands Double Island (New Zealand), one of the Mercury Islands in New Zealand Double Island, Ontario, in Ontario, Canada. References