We present a case of a biliary cystadenoma, a rare benign cystic tumor arising in most cases of the intrahepatic bile ducts. A 30-year old woman presented with abdominal pain in the right upper quadrant for about 10 days with increasing severity. Radiological evaluation by means of abdominal ultrasound and CT-scan revealed a multilocular cystic lesion in the right liver lobe, not present on abdominal ultrasound performed 10 years before. The diagnosis of a biliary cystadenoma was proposed and complete surgical resection of the mass was performed.