Currently, diseases of the reproductive organs remain an urgent problem in pig breeding enterprises with intensive reproduction of livestock. Among them, the most common is postpartum endometritis. According to a number of researchers, the incidence of acute forms of endometritis in sows is 37.6-70.6%, while the prevalence of chronic forms is at the level of 21-27%. This type of pathology is the cause of morbidity and death of piglets from gastrointestinal diseases, and is also the cause of impaired reproductive function and infertility in sows, which leads to premature retirement from the herd. This type of pathology causes considerable harm in the development of the pig breeding sector and causes great economic damage. In pig breeding enterprises, the main therapeutic and preventive solution to this problem is the use of antibiotics and other chemotherapeutic preparations. Nevertheless, it is worth noting that their use is most often carried out uncontrollably and unreasonably, due to this, there is an increase in the number of resistant strains of bacteria, which poses a direct threat to animal and human health. The paper presents the results of the conducted studies, which made it possible to identify the types of bacteria involved in the etiology and pathogenesis of postpartum endometritis and the formation of the symptom complex of postpartum endometritis of sows. Based on the data obtained, it will be possible to further optimize the strategy of therapeutic measures to combat pathogenic microflora.