The hairs of the underparts may be either gray or white at the base and either gray or white at the tip. Aethomys has a ratlike shape, a pointed head, and limbs of equal size. Unlike in species of Rattus that may occur in the same region, in Aethomys the feet are usually white above. The tail may appear to be naked, but it has a light to moderate covering of hairs. Unlike those of Pelomys, the upper incisor teeth of Aethomys are not grooved.
Females have four to six mammae.
These rats inhabit grassland with open scrub, cultivated areas, savannahs, and forest edge. Several species, especially A. namaquensis, favor localities with rocky outcrops or kopjes. A. nyikae has been collected in montane country at an elevation of 2,120 meters. All species are mainly nocturnal and largely terrestrial, though A. chrysophilus and A. namaquensis, at least, are partly arboreal. Shelters include burrows excavated under bushes or rocks, crevices among rocks, holes in termite mounds, and hollow trees and logs.