Pseudomyxoma of the peritoneum is a rare and aggressive disease characterized by the accumulation of mucinous ascites in the abdominal cavity. The article presents a review of the literature, the definition of this disease, its brief history, clinical picture, diagnosis, choice of therapeutic tactics, as well as morphological and molecular features and prognostic factors. The latest therapies, such as cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC), which demonstrate the greatest effectiveness in achieving long-term remission and improving patient survival, are considered. A clinical case illustrating the successful application of these methods in practice is also presented.