The natural borders of the biosphere reserve in the south are Mount Malek Siah and the Ridge of Mount Malek Siah, which form the joint border between Afghanistan, Iran and Pakistan. Mount Chehel-dokhtaran and Mount Palang Kooh constitute the natural limits of the western part of the reserve at altitudes ranging from 1,500 m to 2,000 m.

The reserve is located in the heart of the desert and semi-desert areas of Afghanistan and Iran. Lake Hamoun – a freshwater lake – encompasses marshlands, the watersheds of rivers, canebrakes, algae, insects and several fish species, especially during high-water periods. The reserve is also a hotspot for hundreds of migratory birds, especially wader and water species in eastern Iran. The area is of substantial ecological value due to the important role it plays in protecting landscapes, ecosystems, species and the genetic resources of the region.

The region is home to 55 plant species belonging to 20 families, mostly Chenopodiaceae and Gramineae. Regarding fauna, the area hosts 30 mammal species belonging to 17 families, as well as 183 bird species, 44 reptile species belonging to nine families; seven amphibian species and 22 fish species belonging to four families. Examples include the striped hyena (Hyaena hyaena), the caracal (Felis caracal), the desert monitor (Varanus griseus) and the Dalmatian pelican (Pelecanus crispus).

Lake Hamoun is the biggest freshwater lake located on Iran’s plateau and is internationally registered under the Ramsar Wetland Convention.

Approximately 380,000 people live in the Hamoun Biosphere Reserve. The majority belong to the Sistani group, but Baluchi and Qaeni also live in the area in addition to several nomadic tribes. Fishery, agriculture, handicrafts and straw weaving are the main economic activities.

The area is also known for several sites of historical importance including remnants of Shahr-e-Soukteh, Dahan-e-Gholaman hill and Mount Kooh Khajeh. These hills were important centres of civilization in the Bronze Age.