They may dig their own burrows or seek shelter beneath stumps, logs, or rocks. Several genera live in the hollows of trees, and Euryzygomatomys is apparently fossorial. Thrichomys has been noted in captivity leaping on its hind legs, but the other genera are climbing or scampering animals. Echimyids are reported to be good swimmers. They are usually active in the evening or at night.
Most spiny rats die when exposed to heat and dryness.
The herbivorous diet includes grass, sugar cane, bananas, other fruits, and nuts. Some echimyids consume large amounts of water. These rodents sometimes live in small groups. Various scolding sounds have been noted, but captives are often peaceful. If handled carefully, they do not attempt to bite.