The Himalayan Snow-Cock is a large grey partridge-like bird, 55–74 cm (22–29 in) in length and weighing 2–3.1 kg (4.4–6.8 lb). The head pattern has a resemblance to that of the smaller and well marked chukar partridge. The white throat and sides of the head are bordered by chestnut moustachial stripe and a dark broad chestnut band stretching from the eye over the ear, expanding into the collar. The upper parts are grey, with feathers of the rump and the wings are bordered with rufous. The upper breast is grey with dark crescent bars. The lower breast plumage is dark grey, and the sides of the body are streaked with black, chestnut and white. The undertail coverts are white. The legs and orbital skin are yellow. Sexes are alike in plumage, but the female is smaller and lacks the large tarsal spur of the male. In flight, from above, the white primaries tipped in black and the rufous outer tail feathers make it distinctive. The Tibetan snowcock has a wing pattern with white trailing edge to the secondaries that contrasts with the grey wings.
Around 1841 specimen of a bird was brought to the menagerie of the Zoological Society of London, presented by E W Bonham, consul at Tabrez. George Robert Gray noted that it matched a bird illustrated (plate 76) in Jardine and Selby's "Illustrations of Ornithology" which he noted should be called as Tetraogallus caucasicus and another illustration plate 141 which was said to be the male of the one in plate 76 was separated based on the geography and given the name of Tetraogallus himalayensis. A molecular phylogenetics study suggests that the Tibetan snowcock represents an early or older divergence from the common ancestor of the snowcocks. The main populations are separated by the Taklamakan desert and the separation has been estimated to have happened after the Pleistocene glaciations (1 mya). The large distribution range is fragmented and these disjunct populations show variations in plumage that have been named as subspecies. Although several subspecies have been described, not all are recognized. A subspecies described as sauricus was the subject of considerable nomenclatural debate.
- The nominate subspecies was described by G. R. Gray in 1843 and refers to the populations from eastern Afghanistan extending to Ladakh and the central Himalayas of Nepal.
- incognitus described by Zarudny in 1911 from the mountains of southern Tadjikistan and northern Afghanistan, is overall much paler with very light chestnut and black markings on underside and buffier. (bendi described by Walter Norman Koelz is usually included in this)
- sewerzowi Zarudny, 1910 - Tien Shan to Zaysan (Kazakhstan) east to Xinjiang (not recognized by Ernst Hartert)
- grombczewskii Bianchi, 1898 - Kunlun Mountains
- koslowi Bianchi, 1898 - Nan Shan and Ching Hai Ku Mountains of Qinghai and S Gansu
