Introduction. Fur farming is a cost-effective sector of Russian agriculture, therefore the livestock health issues are relevant. The growth, development and productivity of fur caged breeding animals are affected by various biotic and abiotic factors. Among the biotic factors are diseases, in particular invasive ones, caused, among other things, by ectoparasites. Pathogens associated with ectoparasites often infect fur animals and are widespread. The aim of our work is to study the efficacy of using the medicinal products ExpressTabs® and Inspector Quadro Tabs in treating the otodectosis in foxes in fur farming conditions.Materials and Methods. The study was carried out with 30 caged breeding foxes aged 2 years at Fur Farm “Savvatevo” LLC (Tver Region, Savvatevo village). Foxes were divided into 2 experimental and 1 control groups. Foxes were preliminarily examined clinically, samples of material from the auricles and external auditory canals were taken to find the ear mites Otodectes cynotis. The ExpressTabs® was used in foxes for the first time. The ExpressTabs® and Inspector Quadro Tabs were used according to the instructions, individually, perorally, with a small amount of feed and subsequent observation. To assess the efficacy of the medicinal products, control sampling and microscopy of material from the auricles and external auditory canals were carried out 48 hours, 7 days and 28 days after the start of the experiment. Blood samples were also taken to monitor the parameters before and after administration of the ExpressTabs®.Results. Based on the results of the experiment, we have established the high efficacy of the antiparasitic drugs ExpressTabs® and Inspector Quadro Tabs in treating fox otodectosis in caged breeding conditions. When using the ExpressTabs®, the efficacy was 90% against the ear mite O. cynotis: on the 28th day after the start of using the medicinal product, during the examination of foxes using microscopy, we found only one animal having 4 specimens of O. cynotis in the material from the auricles and external auditory canals, however, all the mites were motionless and without signs of life. The efficacy of the Inspector Quadro Tabs against the ear mite O. cynotis was 80%: on the 28th day, during the examination, only two animals were found to have mites in the scrapings, however, also without signs of life. According to the blood test results, the drug ExpressTabs® proved to have no any pronounced toxic effect on the body of foxes and is safe for use in caged keeping conditions.Discussion and Conclusion. The drugs ExpressTabs® and Inspector Quadro Tabs have shown high efficacy in foxes with otodectosis. These medicinal products can be introduced into the veterinary practices of the fur farms for treating foxes with otodectosis.