Lake Wakatipu is an inland lake in the South Island of New Zealand. It is in the southwest corner of the Otago region, near its boundary with Southland. Lake Wakatipu comes from the original Māori word Whakatipu wai-māori.
With a length of 80 kilometres, it is New Zealand's longest lake, and, at 291 km², its third largest. The lake is also very deep, its floor being below sea level, with a maximum depth of 380 metres. It is at an altitude of 310 metres, towards the southern end of the Southern Alps. The general topography is a reversed "N" shape or "dog leg".