Upper Taz Nature Reserve, Nature reserve in Yamalo-Nenets Autonomous Okrug, Russia.

Upper Taz Nature Reserve is a strict zapovednik in the Krasnoselkupsky District of the Yamalo-Nenets Autonomous Okrug, Russia. It protects the basin of the Ratta River, a tributary of the Taz, across 631,308 hectares divided into the Pokolskoe and Rattinskoe forestries. The terrain is a dissected hilly moraine with ridges averaging 50 metres, and it includes the highest point of the Siberian Uvaly at 285 metres above sea level.

The reserve was established on 24 December 1986 with a total area of 631,308 hectares. It is administered by the Ministry of Natural Resources and Environment of the Russian Federation. Its territory is divided into two forest districts, Pokolskoye and Rattinskoye, which meet along a water-protection clearing on the left bank of the Ratta River.

The Nenets people, an indigenous group from this region, have long moved through this land following their reindeer herds across the tundra. Traces of this nomadic way of life can still be noticed by those who travel through the area with permission.

The reserve is mostly closed to the general public; scientists and environmental-education groups arrange visits with the administration, whose office is in Krasnoselkup, far from the territory. Public ecotourist routes exist but need permits obtained in advance. Guided ecotours run by boat, snowmobile and on foot.

The reserve holds the strictest protection category under IUCN classification, meaning natural processes are left to unfold without any human intervention. This makes it one of the most completely protected places from human and industrial activity anywhere on Earth.