Multicystic peritoneal mesothelioma is an extremely rare benign neoplastic disease with high tendency to recur locally, but no tendency to malignancy. Correct diagnosis can be made with histopathologic examination and always with immunohistochemical and ultrastructural evaluation. A case in a twenty-eight-year-old woman is reported and the anatomo-clinical characteristics of multicystic peritoneal mesothelioma from sixty-nine cases described in the literature are specified, discussing the management of this disease and emphasizing the importance of a nondemolitive approach.