Cockroaches have a broad, flattened body and a relatively small head. They are generalized insects, with few special adaptations, and may be among the most primitive living neopteran insects. The mouth parts are on the underside of the head and include generalized chewing mandibles. They have large compound eyes, two ocelli, and long, flexible, antennae.
The first pair of wings are tough and protective, lying as a shield on top of the membranous hind wings. All four wings have branching longitudinal veins, and multiple cross-veins. The legs are sturdy, with large coxae and five claws each. The abdomen has ten segments and several cerci.