Puku stand about 80 cm (31 in) at the shoulder and weigh from 70 to 80 kg (150 to 180 lb). The puku is sandy brown in colour, with the underbelly a slightly lighter brown. The coat is rougher than that of the similar-sized southern reedbuck, lechwe or impala, or the smaller oribi. Males have horns which are ridge-structured, 50 cm (20 in) long, and lyre-shaped.
There are two subspecies, the Senga Puku (Kobus vardonii senganus) and the southern puku (Kobus vardonii vardonii).