The viper is the largest representative of viper family snakes in the fauna of the former USSR. Body length together with tail can reach almost 2 m, weight up to 3 kg. The head is very large and wide, with sharp neck interception, muzzle is round, pupil and eyes are vertical. Head is covered from above by ribbed scales, and only scales at the end of muzzle without ribs. Supraorbital scales are absent. The number of scales around the middle of the body varies from 23 to 27. Its abdominal scales are 126-181, pairs of sub-tail scales are 33-53, and its anal scales are entire.
The coloration from above is grayish-brown, while pattern varies within the area. The species is monochromatic, almost black or brown, sometimes with purple tint. There is a row of transverse dark brown spots along the back and smaller spots on the sides of the body. Abdomen is light, with small dark spots. The head is monochromatic or with a complex pattern of arcs and spots.