Cook Island Nature Reserve is a protected area in the Australian state of new South Wales located on Cook Island about 600 metres (2,000 ft) off the coastline from the headland of Fingal Head and about 4 kilometres (2.5 mi) south-east of Tweed Heads on the state's north coast.

[2]: 2 The nature reserve consists of the full extent of Cook Island down to the Mean High Water Mark.

It became a nature reserve under the National Parks and Wildlife Act 1967 in 1967.

In 1978, the nature reserve was described as follows:[3]Cook Island provides a breeding habitat for seabirds, in particular the crested tern (Sterna bergii) and the wedge tailed shearwater (Puffinus pacificus).

Due to difficulty of access on to the island the vegetation has maintained its natural condition…The nature reserve is classified as an IUCN Category Ia protected area.