Intraductal papillary neoplasm of the bile duct (IPNB) is a specific type of bile duct tumor. It has been proposed that it could be the biliary counterpart of the intraductal papillary neoplasm of the pancreas (IPMN-P). This hypothesis is supported by the presence of simultaneous intraductal tumors of both the bile duct and pancreas. There have been five reports of patients with simultaneous IPNB and IPMN-P. In all of these cases, biliary involvement was limited to the intrahepatic and perihilar bile duct, which had characteristics similar to IPMN-P and usually had slow progression in nature. Herein, we present the first case of extensive intraductal neoplasm involving the extrahepatic bile duct, intrahepatic bile duct, and entire length of the pancreas with a poor outcome, even after being treated aggressively with radical surgery and adjuvant chemotherapy. Additionally, we summarize previous case reports of simultaneous intraductal lesions of the bile duct and pancreas.