A 64-year-old woman presented with pain in the right hypochondrium since around June, 2003. She was admitted to our hospital. CT showed swelling of the gallbladder and dilation of intrahepatic bile duct down to superior bile duct. In addition, the body and tail of pancreas was replaced with fat. MRCP and ERCP showed the tubercle-shaped filling defect in the common bile duct and dilation of the superior bile duct in fusiform with a diameter of 2cm. In addition, there was pancreaticobiliary duct maljunction. She underwent surgery with the diagnosis of bile duct cancer associated with pancreaticobiliary duct maljunction with fatty replacement of pancreatic body and tail. Histopathologically, the tumor was papillary adenocarcinoma, invasion depth ss, no metastases to lymph nodes. Postoperative course was uneventful, and she is alive 16 months after the operation.