Hemobilia is relatively rare among hemorrhages in the digestive tract, and hemobilia caused by tumors of the biliary tract is particularly rare. We treated a 74-year-old-man with undifferentiated carcinoma of the gallbladder presenting with hemobilia. During hospitalization for neurogenic bladder at the Department of Urology, he showed progressive anemia. Since hemorrhage in the digestive tract was suspected, endoscopy of the upper gastrointestinal tract was performed, and bleeding from the papilla of Vater was observed. On ultrasound examination, findings were indicative of cholecystic cancer, and hemorrhage from the cystic duct was found on percutaneous transhepatic cholangioscopy. On perioral cholecystoscopy, however, masses of coagulated blood were found only in the gallbladder. Abnormalities such as dense staining of tumors or extravasation were not found on angiography. The patient died of hepatic failure due to rapid invasion of the liver by the tumor, associated with biliary infection and disseminated intravascular coagulation. At autopsy, a nodal tumor was found in the gallbladder, and the cavity of the gallbladder was filled with coagulated masses of blood. Direct invasion of the tumor to the liver, diaphragm, and transverse colon was found. The histopathological diagnosis was undifferentiated carcinoma (pleomorphic large-cell type).