Juist () () is an island and municipality in Aurich in Lower Saxony in Germany. The island is one of seven East Frisian Islands at the edge of the Lower Saxon Wadden Sea in the southern North Sea. It is between Borkum Island (west), Memmert Island (southwest) and Norderney (east). The island is long and from to wide, depending on the tide levels. There are two villages on the island: the main village Juist, and Loog. The island is separated from Norderney by the Norderneyer Seegatt.