The peritoneal mesothelioma is a rare neoplasm which arises from the peritoneal lining of the abdomen, tending to spread along the peritoneal cavity and to invade abdominal organs. authors report the CT findings of 4 patients with histologically proven peritoneal mesothelioma seen at Dongsan Medical Center, School of Medicine, Keimyung University. None of them had a history of exposure to asbestos and no clear etiologic factor could be determined in any patient. CT showed peritoneal and mesenteric thickenings in all cases, omental thickenings in 3 cases, peritoneal nodules, mesenteric masses or omental masses in 2 cases each other, bowel wall involvement in 1 case, and disproportionally small ascites in 2 cases. Distant hematogenous metastases to the liver and retroperitoneal lymph nodes were seen in 1 case. Our experience with 4 peritoneal mesotheliomas as well as a review of the recent imaging literature shows excellent correlation between computed tomography and the operito eoscopic findings.