The Great Lakes Depression (Mongolian: Их нууруудын хотгор, Ikh Nuuruudyn Khotgor), also called the Great Lakes' Hollow, is a large semi-arid depression in Mongolia that covers parts of the Uvs, Khovd, Bayan-Ölgii, Zavkhan and Govi-Altai aimags.

Bounded by the Altai in the West, Khangai in the East and Tannu-Ola Mountains in the North,[1] it covers the area of over 100,000 km2 (39,000 sq mi) with elevations from 750 to 2,000 m (2,460–6,560 ft).

The wetlands are based on the system of interconnected shallow lakes with wide reed belts within a generally desert steppe.

The wetlands support a number of rare migrating birds: Eurasian spoonbill (Platalea leucorodia), black stork (Ciconia nigra), osprey (Pandion haliaetus), white-tailed eagle (Haliaeetus albicilla), swan goose (Cygnopsis cygnoides), and bar-headed goose (Anser indicus).

[2] Although the total number of fish species in the region is low, a large percentage of those that do occur are endemic or near-endemic, especially from the genera Oreoleuciscus (Altai osmans), Thymallus (graylings) and Triplophysa (a stone loach genus).