Mount Cook area from LandSat. The Tasman Glacier is at top right

The Tasman Glacier is the largest of several glaciers which flow south and east towards the Mackenzie Basin from the Southern Alps in New Zealand's South Island. It is 27 kilometres long and as much as three kilometres wide, and is entirely within the borders of Aoraki/Mount Cook National Park.

The Tasman flows south from the southern slopes of the Minarets peak, along the eastern flank of Mount Cook, the peak of which is only five km from the glacier. It is met partway along its length by the meltwater of the Murchison Glacier, which joins from the northeast.

The waters from both these glaciers, along with those from the nearby Hooker and Mueller Glaciers flow into the wide valley of the Tasman River, whose braided streams flow south into Lake Tekapo. They eventually flow through the Waitaki River to the Pacific Ocean north of Oamaru.