Aim: to conduct a morphological evaluation of the effectiveness of probiotic disinfectants for abdominal cavity sanitation in experimental widespread peritonitis. Materials and Methods: The experimental study was conducted on 45 white male Wistar rats aged 4-5 months, which were modelled with peritonitis. The rats were divided into 3 groups of 15 animals each. The treatment of animals in the main group (group I) consisted of washing the abdominal cavity with a 5% solution of probiotic disinfectant, applying a probiotic disinfectant spray and a gel with probiotics to the surgical wound. For the treatment of rats in the comparison group (group II), a sorbent solution was used. The treatment of rats in the placebo control group (group III) consisted of abdominal lavage with 0.9% NaCl. Histological, histochemical and immunohistochemical studies were performed. Results: In the main group, 10 (66.7 %) rats survived, in which peritonitis was eliminated, as evidenced by clinical and morphological results. In the comparison group, 8 (53.3 %) rats survived, in which peritonitis was eliminated. All animals in the placebo control group died of severe peritonitis. The best repair and renewal of mesothelial cells with a pronounced intensity of parietal peritoneal expression was in group I. In group II on the 7th day there were mesothelial cells with moderate expression, in group III - there was a weak intensity of expression in single cells. Conclusions: According to our data, probiotic disinfectants are effective for abdominal cavity sanitation in peritonitis, which was proved by experimental study.