Pyemotidae mites are ectoparasites of a large number of arthropods, and Pyemotes tritici (Acari: Pyemotidae) is often found parasitizing insects in various habitats, including in the laboratory. Here we report widespread infestation of P. tritici in laboratory colonies of various species of stored-products insects. P. tritici infestations were observed in laboratory colonies (MIPGrains/UFV) of Sitophilus zeamais (Coleoptera: Curculionidae), Alphitobius diaperinus (Coleoptera: Tenebrionidae), Lasioderma serricorne (Coleoptera: Anobiidae), Acanthoscelides obtectus (Coleoptera: Bruchidae), Rhyzopertha dominica (Coleoptera: Bostrichidae), Ephestia sp. (Lepidoptera: Pyralidae), and Tribolium castaneum (Coleoptera: Tenebrionidae). The widespread infestation of P. tritici in laboratory colonies of these species is a serious problem. This mite can substantially reduce insect populations or even kill them, making it impossible to rear the insects, as observed in this research. This ectoparasite is not recommended as a biological control agent in integrated pest management of stored-product pests because P. tritici can attack bees, mammals, and other animals and cause dermatitis in humans. In consideration of the above, the ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 19 (3): gmr18548 A.H. de Souza et al. 2 widespread infestation of P. tritici in colonies of S. zeamais, A. diaperinus, L. serricorne, A. obtectus, R. dominica, Ephestia sp., and T. castaneum indicates that this mite should be monitored when raising stored-products insects to ensure the development of the insect populations and ensure that the laboratory environment is safe.