Bestial flies are widely spred at various types of livestock enterprises (dairy farms, fattening farms, pig farms, sheep farms, stud farms, poultry farms) of the Russian Federa-tion; they are mechanical and biological carriers of many pathogens of infectious and invasive diseases, can cause anemia and stress in productive farm animals and young animals. The economic damage from infec-tious and parasitic diseases, the causative agents of which carry licking and blood-sucking flies, as well as from a decrease in productivity due to stress, is measured in hundreds of millions of rubles a year. In addition, high costs are required for veteri-nary, anti-epizootic and recreational activi-ties. We conducted a test to study the effective-ness of the Flyblock® food pellet bait (organization-developer of NEC Agrovet-zashchita LLC), an insecticidal and attract-ant measurement during the period of the maximum number of bestial flies on a pig farm.The food bait was tested from the sec-ond half of summer until the end of Septem-ber in three commercial pig farms of the Ryazan Region: 50 x 12 m - experimental, 5 x 12 m - control № 1 (fodder kitchen), 50 x 12 m - control № 2. In the experimental room, the Flyblock® drug granules were distributed by the rate of 5 g per 5 m2 in cardboard containers 12 x 8 cm in size with 4 cm high side walls in plac-es not accessible to animals - window open-ings. The Flyblock® pellet food bait was placed once with regular monitoring (starting from the first day and for 2.5 months) of its effectiveness against bestial flies with the obligatory re-moval of dead flies. Studies have showed the high efficiency of Flyblock® food pellets against bestial flies. The effectiveness of the the drug against licking and bloodsucking flies when keeping pigs for fattening in the premises of a com-mercial pig farm is in almost all cases of research more than 95%.