Pest Identification

Learn More About the Pests Invading Your Home

Oriental Cockroach




How to exterminate them


The key to exterminating large roaches like Oriental cockroaches is to kill the entire roach nest. If you just spray and kill the individual roaches that you see, you will continue to see roaches scampering around your home looking for food and water, and will most likely begin to see more of them and more frequently as they breed and the nest continues to grow. Combat® products provide the source kill you need and are a guaranteed solution! Use Combat® Source Kill Max Large Roach Baits in common areas where you see roaches and Combat® Combat Source Kill Max Roach Killing Gel in cracks and crevices or places where roaches might enter the home. Click here to learn more about how Combat® works to kill at the source.


Where they live


Oriental Cockroaches are major household pests in parts of the Northwestern, Midwestern and Southern United States. Unlike most large cockroaches, they live in temperate regions and do not survive in tropical climates. They are sometimes called “black beetles” or “water bugs” because of their dark coloring and their preference for damp locations.


What they look like


Oriental Cockroaches are large roaches. They are dark-brown to black in color and adults are approximately 1 to 1 1/4 inches long. Adult males have fully developed wings reaching 3/4 of the way down their backs, but do not fly. Females have undeveloped wings, which are reduced to small lobes.


Where they nest


Oriental Cockroaches are commonly found during the spring and summer in dark and damp areas outdoors. They typically invade homes through drains or small cracks and are commonly found in basements and crawl spaces. They will climb to upper floors and often climb into apartments through garbage chutes in multistory buildings.


Steps to prevent an invasion


Reduce access to the home or other structures by caulking cracks in exterior walls and installing screens in drains. Increase ventilation and sunlight by trimming back shrubs will discourage Oriental Cockroaches from settling in basements and crawl spaces. Decrease damp areas in the yard by limiting irrigation, improving drainage, and removing piles of wood, leaves, or other debris.




Fact Sheet

  • Oriental cockroaches are considered large roaches and are about 1 inch in length
  • They have a greasy sheen
  • They are known for their strong, unpleasant, “roachy” odor and they actually emit a foul odor due to the numerous bacterial and viral pathogens on their bodies
  • Oriental cockroaches love water
  • They prefer to live outdoors but will go indoors during the summer time
  • Male Oriental cockroaches are small and have wings and females are larger without wings but neither males or females can fly