Abstract : Pseudomyxoma peritonei (PMP) is a rare condition that refers to a clinical syndrome resulting from the accumulation of mucin in the peritoneal cavity. It results from the intraperitoneal rupture of a mucinous epithelial neoplasm which is classically appendiceal. The prognosis of a limited appendiceal tumor is favourable. Nevertheless, in the case of peritoneal dissemination, the prognosis could be different according to the histological type and therapeutic management. We report the case of a 71-year-old female patient who developed a pseudomyxoma peritonei originating from an appendiceal adenocarcinoma.