The problem of studying the pathology of mesenteric fat of the small intestine in surgical practice has not yet received enough attention. A number of questions remain unresolved regarding the etiology and pathogenesis of mesenteric diseases, their possible connection with benign and malignant diseases, methods of their laboratory and instrumental diagnosis, possible options for conservative and surgical treatment, as well as systematization and structuring of the classification. One of the poorly studied representatives of diseases of the mesentery of the small intestine continues to be Sclerosing mesenteritis, characterized by various histological variants of damage to mesenteric fat and a varied nonspecific clinical picture. Taken together, this leads to certain difficulties in diagnosis, patients seeking access to doctors of various profiles, which ultimately negatively affects the results of treatment and can lead to social maladjustment and possible disability. Reports on the occurrence of this pathology in the medical literature are few and, as a rule, describe extremely rare clinical cases. However, in recent years, the frequency of detection of this pathology continues to grow steadily, which is associated with the progressive aging of the population, a high degree of surgical activity in relation to urgent diseases of the abdominal organs, and the improvement of instrumental diagnostic methods. Issues of etiology, pathogenesis, differential diagnosis of this disease and its possible connection with the paraneoplastic process currently continue to cause debate. Further accumulation of clinical experience, a better understanding of the pathogenesis of the disease, and improvement of imaging techniques will allow us to develop clearer diagnostic and clinical criteria, narrow the diagnostic search and, ultimately, improve and standardize treatment. The article provides a review of the literature on this rare surgical pathology, presents our own clinical observation, and discusses diagnostic issues and treatment options for this disease.