In some species the coat is full, long, and soft, while in others it is short and harsh. The tail and ears are brown. Zygodontomys resembles Oryzomys but may be distinguished by its relatively shorter tail and shorter hind feet. The anterior nails of Zygodontomys are smaller than those of Akodon. The ears of Zygodontomys are small.
Females have eight mammae.
These animals live in open country and in areas of low bushes and thick ground cover, usually near water, from sea level to about 600 meters in elevation. They make runways through the dense grass and are active at night. Nests are made of grass and the down of flowers. These are built at the ends of short burrows in banks or under tree roots. The young opened their eyes after about 7 days and were weaned at 9-11 days.