The aardwolf is slightly larger than a jackal or a fox and has long, slender legs and a long neck. Its sloping back is not as pronounced as in the three other hyaena species. The background colour of the body varies from yellowish-white to rufous. The throat and underparts are paler and can reach a greyish-white color. There are three vertical black stripes on the body and one or two diagonal stripes across the fore- and hindquarters. Irregular horizontal stripes run across the legs, which are darker distally, and grade into solid colored feet. Sometimes black spots or stripes are present on the neck. Having stripes on the body, the aardwolf superficially resembles the striped hyaena, but it is less than half the size and its stripes are much more regular than those of the striped hyaena. Facial hair is very short and gray. The muzzle lacks hair and is gray-black in color. Proteles cristata has a dense undercoat with coarse guard hairs. It also has a black mane extending from head to tail which can be erected to make the individual appear larger when threatened (Koehler and Richardson, 1990; Richardson and Bearder, 1984). There are five digits on the front feet (the other members of the Hyaenidae have only four), and four on the hind feet (Koehler and Richardson, 1990; Richardson and Bearder, 1984).
In southern Africa, adult body mass varies seasonally with the availability of termites, and averages around 8-10 kg (Anderson 1994) with little variation between sexes. Adult body masses of up to 14 kg have been reported in East Africa (Kingdon 1977). Head to tail the aardwolf measures 0.95 m (0.85-1.05 m) and stands 0.475 m (0.45-0.5 m) at the shoulder (Smithers 1983, Koehler and Richardson 1990).
The size of P. cristata helps to separate it from its closest relatives, subfamily Hyaeninae or bone-cracking hyaenas. Proteles cristata is significantly smaller than all other hyaenas with a body length of 0.85 to 1.05 m, tail length of 0.2 to 0.30 m, and a shoulder height of 0.45 to 0.5 m. There is no sexual dimorphism in the body size of P. cristata.
The aardwolf has strong jaws and canine teeth, but its cheek teeth have been reduced to pegs, and can vary in number. Ears and eyes are very large for the animal’s size. It has a very broad tongue and produces sticky saliva used in myrmecophagy (Koehler and Richardson, 1990; Richardson and Bearder, 1984; Richardson, 1987c).