King Island, Kings Island or King's Island may refer to:

Australia

• King Island (Queensland)
• King Island, at Wellington Point, Queensland
• King Island (Tasmania)
  • King Island Council, the local government area that contains the Tasmanian island

Canada

• King Island (British Columbia)
• King Island (Nunavut)
• King Island (Saskatchewan)
• King Island, Newfoundland and Labrador, a settlement

United States

• King Island (Alaska)
• King Island (California)
• Kings Island (California)
• King's Island (Connecticut)
• King's Island (Pennsylvania)
• Kings Island, amusement park in Mason, Ohio

Elsewhere

• Kadan Kyun, formerly known as King Island, in Myanmar's Mergui Archipelago
• King Island (New Zealand), island off the north coast of the North Island
• King's Island, Limerick, Ireland, an area of Limerick city
• King Peninsula, Antarctica, originally believed to be an island ("King Island") but later discovered to be a peninsula