It is a high granite island about 7 square kilometres in size.
There are three smaller islands nearby (Palfrey, South and Bird).Together these form the Lizard Island Group and their well-developed fringing reef encircles the 10 metre deep Blue Lagoon. The only settlements on the island are the Research Station, the Lizard Island Resort and a basic camping area operated by the Queensland Parks & Wildlife Service.
All islands in the Lizard Island Group are part of the Lizard Island National Park, administered by the Queensland Parks and Wildlife Service. Lizard Island is situated in the waters of the Great Barrier Reef Marine Park, administered jointly by the Great Barrier Reef Marine Park Authority and the Queensland Environmental Protection Agency. Permits are required for all research conducted in the Lizard Island Group and the waters surrounding it.
The Lizard Island Group is a mid-shelf reef, situated 30 kilometres from the Australian mainland and 19 kilometres from the outer barrier reefs that line the edge of the continental shelf. Most reef and island types characteristic of the Great Barrier Reef are accessible from the Research Station.