Peritonitis is still an urgent problem and its solution is determined to a great measure by purposeful studies in the field of pathogenesis and treatment. The creation of adequate models of peritonitis acquires particular significance. Eighty-four animals (dogs) were used to create the model. It is shown in the work that a standard model of generalized peritonitis can be produced by two injections of a polymicrobial suspension consisting of the most commonly encountered peritoneal microbes E. coli and B. fragilis. The suspension is injected into different levels of the abdominal cavity. With this method of administration of the polymicrobial suspension the model was reproduced in 90% of cases. Thus, the developed model resembles human peritonitis in the clinical picture and the laboratory and morphological values.