Chronic catarrhal gingivitis is a polyetiological disease, in the pathogenesis of which the main role belongs to the microorganisms of the oral cavity of the dog, odontogenic deposition in the form of dental plaques and tartar. These depositions, due to the constant irritation of the gums cause disease, the main clinical signs of which are halitosis, poor feed intake, swelling and bleeding gums. The problem of chronic catarrhal gingivitis treatment is devoted to numerous inverstigations, the priority of which is a comprehensive approach, which includes a step-by-step influence on the etiological and pathogenetic mechanisms of the disease. Therefore, the purpose of the work is to study the features of the course of chronic catarrhal gingivitis and to develop a method for the treatment of dogs with dental disease. The prevalence gingivitis in dogs, the influence of microflora on the condition of the oral cavity in chronic catarrhal gingivitis, was investigated the symptomatology of the disease, was established the value of clinical indicators and dental indices and tests, which reflect the intensity and nature of the inflammatory process in the gums of dogs suffering from chronic catarrhal gingivitis, and a method of treating dental animals was developed. The results of the inverstigations showed that the application by application to the mucous membrane of gums 0.05% solution of chlorhexidine and a gel composition of 4% chitosan ascorbate with metronidazole, and also feeding once a day for 30 days of the vitamin-mineral supplement “Canvit Biocal Plus” in the complex treatment of dogs with chronic catarrhal gingivitis helps to reduce the recovery period of dogs by 5 days.