Brass's Brush Mouse is a rodent recorded in riverine and hill forests of south-central New Guinea. Its back is grayish brown and its underside is white.
The dorsal fur is grayish brown and lighter on the sides; the underside is pure white. Its feet are very broad and white, with a brown streak on the upper side of each hindfoot.
Its habitat is lowland tropical moist gallery forest and hill forest. HMW 2017 says it is probably arboreal and nests in tree hollows.
An extinction-risk assessment has not been added yet.