The purpose of the research is to study the efficacy of the drug in the form of spray based on Fipronil, Moxidectin and Pyriproxyfen against canine acarosis.Materials and methods. The assessment of the acaricidal effect of multicomponent drug against canine acarosis was carried out on the basis of the All-Russian Scientific Research Institute of Infectious Diseases (VNIIP), a branch of the Federal State Budgetary Institution FSC VIEV RAS, as well as the veterinary clinic GLOBALVET CLINIC LLC (Moscow) in 2020–2022. 82 dogs were used in the experiments, including those spontaneously infected with Otodectes cynotis (38 sp.), Sarcoptes canis (28 sp.), and Demodex canis (16 sp.). The animals were divided into experimental and control groups. To the infected animals of the experimental groups, the drug was applied in the form of spray to the affected areas of the body at the rate of 1 ml per 10 cm2, 2–4 times with an interval of 7 days. The dogs in the control group were treated at the end of the experiment. The efficacy of the drug was taken into account by examining and recording the number of ticks in animals before and 3, 11, 25, 40 and 60 days after treatment. The results were processed statistically using Microsoft Excel.Results and discussion. On the 11th day, all animals showed extinction of clinical signs, healing of affected skin areas and scratches, and the appearance of new hair in areas of alopecia; microscopy of scrapings revealed single mites, deformed larvae and eggs. Microscopy of skin scrapings on the 25th day revealed single mites in 5 dogs affected by demodicosis. On the 40th day, upon examination and acarological examination of animal skin scrapings, no S. canis, O. cynotis and D. canis mites were found. The research results showed 100% efficacy of the drug.