Biloma is an infrequent complication of nonsurgical treatments of hepatocellular carcinoma (HCC), including transarterial embolization (TAE), and it is often associated with ischemic injuries of the biliary tract after therapy. We here report on a case featuring successful internal drainage of an extrahepatic biloma into the duodenum by a route via the cholecyst, cholecystic duct, and common bile duct under fluoroscopic control. An extrahepatic biloma developed after urgent TAE for ruptured HCC and became contaminated. Radiography with contrast medium through the percutaneous drainage tube revealed a fistula between the biloma and gallbladder. The drainage catheter was introduced into the gallbladder through the fistula, from where it subsequently reached the duodenum via the cholecystic and common bile ducts. The internal drainage route played a major role in the rapid elimination of the biloma, which did not recur after the tube was withdrawn. To our knowledge, this is the first report of internal drainage of a biloma through the cholecystic and common bile ducts.