Shag Island may refer to:
Shag Island (South Australia), South Australia Shag Reef, Tasmania, Australia Tarahiki Island, also known as Shag Island, Hauraki Gulf, New Zealand Shag Islands, Newfoundland, Canada Shag Islet, a small island 10 km north of Heard Island.
See also Shag Rock (disambiguation) Shag Rocks (disambiguation) Shag Reef