Situated in the Saharan region of Niger, approximately 160 km north-east of Agadez, the reserve includes a smaller core area integral reserve called Sanctuaire des Addax.
The reserve lies in an arid region of the Sahara, with average rain fall of around 50 mm per year. It is composed of two main zones: the mountain massifs of the Air rising to 2,000 m in altitude, and the extensive flat plain of the Ténéré desert. Habitats are diverse, ranging from aquatic communities in the permanent rock pools (gueltas ) of the mountains, to heavily-wooded valleys and open sandy desert. The Air Mountains are basically a Sahelian enclave surrounded by a Saharan environment, but Sudanese and Mediterranean elements are also present.
The relict Sudanese and Mediterranean elements are found above 1,000 m in the sheltered wetter localities in the massifs. Sudanese species include Grewia and several species of Ficus . Mediterranean species include the wild olive. The reserve harbours significant populations of the wild relatives of several important crop species: wild olive, millet and sorghum.
40 species of mammal, 165 birds, 18 reptiles and one amphibian from the reserve have been identified. Significant populations of several internationally threatened Saharan desert ungulate species are present: there are an estimated 12,000 Dorcas gazelle, 170 Dama gazelle, 3,500 Barbary sheep (aoudad ), occasional addax and possibly slender-horned gazelle. Carnivores include healthy populations of fennec fox, Ruppell's fox, and a small and probably declining population of 15-20 cheetahs. About 85 of the bird species recorded are Palaearctic migrants; of the remainder the estimated 800-2,000 ostrich represent the last viable population of the West African race, and there are substantial numbers of Nubian bustard. The reptilian fauna includes the desert monitor lizard, the sand viper and various species of sand boa and gecko.
Palaeolithic and Neolithic archaeological sites are found at many locations in the reserve, as are rock engraving sites. The 3,500-7,000 Twareg inhabitants for the most part maintain a lifestyle of transhumant pastoralism, raising goats and camels. The settled population practises irrigated agriculture, growing wheat, fruit, vegetables and dates.