It appears that the ancestors of this species fed on dead insects and other animals. However, over the years they started feeding on plant products as well.
Because of its voracious appetite, the warehouse beetle is now considered to be one of the most harmful stored food pests. It attacks many types of foodstuffs, including broccoli, cantaloupe, and carrot seeds, cake mixes, pasta, cookies, flour, cereal, rice, dried foods, candies, peanuts, and even dry dog food.
Still today, warehouse beetles are found feeding on dead insects and other animals. Larvae have even been observed eating dead warehouse beetle adults. Old rodent bait can also be a food source for these insects.
Unlike other species of dermestids, the warehouse beetle is a good flyer and can easily move about. Specimens have been collected as high as 10.5 m (35 ft.) in the air.
Warehouse beetles are attracted by light and are often found on window sills and skylights. Electric light traps have been found to be very effective as a monitoring tool in warehouses.