Experimental substantiation of a new method of antireflux small-intestinal anastomosis forming by means of histomorphological, biochemical envestigation of the mucous tunic of gastrointestinal tract, as well as feces of mongrel dogs and rabbits is presented in the article. It has been established that formation of the suggested anastomosis leads to a rapid renewal of the mucous barrier of the large and small intestines, manifested in an increase of quantity of functionally active gobletcells and glycocalyx. An increase of the activity of succinate dehydrogenase, alkaline and acid phosphatase of the mucous tunic of the distal part of the small intenstine is also marked, that is evidence of intensity of compensatory processes’ course and rapid formation of compensatory changes. Coprograma of the animals, to which the suggested small–intestinal anastomosis was performed, is characterized by prevalence of the per cent of animals in which invariable muscular fibre, plant cellular tissue of starch, neutral fat were not revealed, that also demonstrates better course of compensatory processes and rapid formation of compensatory changes.