Groote Eylandt is the largest island in the Gulf of Carpentaria in northeastern Australia. It is the homeland of, and is owned by, the Anindilyakwa people who speak the isolated Anindilyakwa language.
Groote Eylandt lies about 50 km from the Northern Territory mainland and eastern coast of Arnhem Land (about 630 km from Darwin), opposite Blue Mud Bay. The island measures about 50 km from east to west and 60 km from north to south; its area is 2,326.1 km². It is generally quite low-lying, with an average height above sea level of 15 m, although Central Hill reaches an elevation of 219 metres. Its geographic coordinates are . It was named by the explorer Abel Tasman in 1644 and is Dutch for "Large Island" in an archaic spelling. The modern Dutch spelling is Groot Eiland.