Oriental cockroaches are usually black to dark brown, and are fairly large-but smaller than the American cockroach at about 1¼ inches in body length. They can become numerous in damp, secluded areas such as crawl spaces, basements, and drains, and are occasionally called "water bugs" by mistake. The oriental cockroach is often found in a bathtub because it lacks sticky pads on its feet and cannot climb the smooth sides.

Oriental cockroaches are also found outside near water sources or in the garage, being quite adept at living outdoors. These roaches are quite common in the sewers, and may come into houses through the drains. If the crawl space under a house is damp, it becomes an excellent breeding location for these roaches. The Oriental cockroach has a bad odor that people associate with cockroaches. They will eat any human or pet food, garbage, or other organic materials.

The female produces about eight egg capsules in a lifetime with each containing 16 eggs. She deposits this capsule within 30 hours after its produced. The nymphs emerge and go through 7-10 molts before becoming adults. There is usually only about one generation per year, which can take well over 500 days to complete. The adults will live about a year.