The New Caledonia Biodiversity Hotspot is located in the South Pacific, 1,200 kilometers east of Australia. The hotspot consists of the main island of Grande Terre and the smaller Loyalty Islands to the east, Belep Islands to the north and Isle of Pines to the south. The Chesterfield Islands further to the west, and the uninhabited volcanic islands of Matthew and Hunter to the east, which are politically dependent on New Caledonia, are also included.

New Caledonia's ecosystems include several natural vegetation types, evergreen rainforests—which once covered about 70 percent of the area —among them. Today grassland and niaouli (Melaleuca quinquenervia) savanna occupy more than 32 percent of the hotspot, and are often mistaken by visitors and residents as the typical landscape of New Caledonia. These are, in fact, a result of human activity, maintained by repeated fire and grazing by cattle and introduced deer.