A 78-year-old man with hepatocellular carcinoma treated by chemoembolization and percutaneous ethanol injection was admitted to our hospital because of acute abdomen. The CT scan showed biliary fistula caused by hepatocellular carcinoma protruding from S3. Endoscopic retrograde cholangiopancreatography showed disruption of an intrahepatic duct and the main pancreatic duct, and contrast agent leaked into the peritoneal cavity from each duct Omental panniculitis with biliary fistula and pancreatic fistula was diagnosed. The symptoms improved by endoscopic nasobiliary drainage and endoscopic pancreatic stenting. On the 13th day after admission, we added endoscopic nasopancreatic drainage because his abdominal pain had been exacerbated by pancreatic juice leakage. Omental panniculitis by hepatocellular carcinoma complicated by biliary fistula and pancreatic fistula is extremely rare. Endoscopic transpapillary pancreaticobiliary drainage was effective for omental panniculitis in this case.