The upper parts are brown mixed with red and black, and the underparts are reddish. The external form is somewhat volelike. The tail is short, dark, and somewhat hairy. The skull is broad and massive, and the head is broad and rounded. The ears are well haired, and the palms are dark.
Females have three pairs of mammae.
Brachyuromys has been trapped in a large, moist meadow on the central plateau of Madagascar. The animals were living in dense, matted grass and reeds, in association with Microgale, Eliurus, and Rattus. The grass and reed stems were so matted down and so densely tangled that no sunlight reached the runways where the mice were traveling. They were active at all hours during both the night and the day.