Noatak National Preserve is a United States National Preserve in northwestern Alaska that was established to protect the Noatak River Basin. The Noatak River system, located just north of the Arctic Circle, is thought to be the last remaining complete river system in the United States that has not been altered by human activities. The roadless basin was proclaimed a United States National Monument in 1978 and a National Preserve in 1980 through the passage of the Alaska National Interest Lands Conservation Act (ANILCA). Noatak National Preserve borders Kobuk Valley National Park on the south and Gates of the Arctic National Park on the east. Unlike the national parks that it borders, sport hunting is allowed in Noatak National Preserve.

All of the preserve, except for about 700,000 acres (280,000 ha) east of the village of Noatak, has been designated the 5,765,427-acre (2,333,186 ha) Noatak Wilderness. The wilderness is the fourth-largest in the United States, following the Wrangell-Saint Elias Wilderness, the Mollie Beattie Wilderness, and the Gates of the Arctic Wilderness.

The preserve includes the transition zone from boreal forest to tundra near the southern edge of the preserve. The Noatak Basin is a transition zone for plants and animals between Arctic and subarctic environments. The lower portion of the Noatak valley has areas of boreal forest, but most vegetation is low-growing tundra species. Alpine tundra occurs at high elevation, and moist tundra, the most common condition, supports cottongrass, willows, Labrador tea, mountain alder, dwarf birch and other tundra species at lower elevations. Boggy areas support cranberry, bog rosemary and salmonberry.

Wildlife of the Noatak tundra includes Alaskan moose, grizzly bears, black bears, wolf packs, Arctic foxes, lemmings, Dall's sheep, vast herds of caribou numbering more than 230,000 individuals, and a variety of birds. Larger birds include Canada geese, tundra swans, white-fronted geese and common, Arctic, yellow-billed and Pacific loons. Predatory birds include rough-legged hawks, gyrfalcons and golden eagles.

The central feature of the preserve is the Noatak River, and is a breeding ground for a variety of commercially important fish. The most widespread salmon species is chum, and pink, chinook and sockeye salmon are found as well. Several kinds of trout are found in deep lakes, with Arctic char and Arctic grayling the most common salmonids in the preserve. Burbot are also found, as are nelma or sheefish, an important species for subsistence fisheries.

The Brooks Range has existed since Cretaceous time, and is composed mainly of shales, limestone and chert, with intrusions of igneous rocks from more recent volcanism. The valleys are composed of limestone, sandstone and siltstone, with deposits of sand, gravel, silt and clay. During the Wisconsonian glaciation the area was incompletely covered by ice, with higher regions glaciated. Permafrost exists in higher regions, becoming patchy at lower levels.

Since Noatak is a national preserve, both subsistence hunting by local residents and sport hunting by outsiders are permitted in the preserve. If Noatak was a national park, only subsistence hunting would be allowed. Float trips on the Noatak River are a popular way to see the preserve. However, most trips on the Noatak River take place high on the river in Gates of the Arctic National Park, typically from Twelve Mile Creek to Lake Matcherak. Longer trips can continue through the preserve, although the lower river's braided stream presents difficulties beyond Noatak village. There are a few rapids on the river of Class II+, although most of the river is Class I or Class II. Float trip season runs from June or July, when the river thaws, to September. Biting insects are most prevalent in June and July.

The 6,569,904-acre (2,658,746 ha) preserve extends westward from Gates of the Arctic National Park along the Brooks Range to the north and the Baird Mountains to the south, enclosing the valley of the Noatak River. It is bordered to the north by the National Petroleum Reserve–Alaska. The lower valley of the Noatak is not part of the preserve, separating the preserve from Cape Krusenstern National Monument on the coast. The southeast corner of the preserve runs almost to the coastline at Hotham Inlet. The distance from the headwaters in Gates of the Arctic National Park to Noatak, Alaska is about 354 miles (570 km). Land ownership within the preserve is mostly federal, with 289,973 acres (117,348 ha) owned by native corporations or under easements.