The mucin-hypersecreting bile duct tumor is rare and its clinical, radiologic, and pathologic features are not well known. We report the case of mucin-hypersecreting biliary papillomatosis with malignant transformation including review of 11 korean literatures. A 65-year-old female was admitted to our hospital with fever, chills, and right upper quadrant pain. A CT scan showed marked dilatation of left intrahepatic duct with intraductal filling defects. During endoscopic retrograde cholangiograpy, mucin from the ampulla was observed and dilated common bile duct with multiple amorphous filling defects was noted. Cholangioscopy revealed muliple coral-like mucosal papillary projections with large amount of mucin in the left intrahepatic ducts. The patient underwent left lobectomy, and the biopsy revealed intraductal papillary adenocarcinoma in the background of papillary adenoma.