Male and female pheromones of Trogoderma granarium Everts produce a reaction in 5 other species of insects. Statistical analysis of the results shows that the intensity of the response to male and female pheromones can be arranged in the following sequence: Tenebrio molitor L. > Tribolium castaneum (Herbst) Trogoderma granarium > Dermestes maculatus De Geer > Oryzaephilus surinamensis (L.) > Callosobrnchus maculatus (F.). Tenebrio molitor, Tribolium castaneum, D. maculatus, and O. surinamensis are repelled by the substances, while Trogoderma granarium and C. maculatus are attracted (the latter only to the female extract). Sitophilus oryzae (L.), Lasioderma serricorne (F.), and Ephestia cautella Walker are indifferent to the pheromone. At threshold concentrations of the Trogoderma granarium pheromone for T. granarium response, the beetles Tenebrio molitor and Tribolium castaneum still show a very high response.