Northbrook Island (Russian: остров Нортбрук) is an island located at 79°54′N50°54′E / 79.9°N 50.9°E / 79.9; 50.9 in the southern edge of the Franz Josef Archipelago, Russia. Its highest point is 344 m.
Northbrook Island is one of the most accessible locations in the island group. Thus it often served as a base for polar expeditions in the late 19th and early 20th centuries.