Clonorchiasis is the common disease of liver fluke found in east asia including korea. In clonor- chiasis, obstruction of bile duct occur by adult ivorm, biliary stone and adenomatous hyperplasia of ductal epithelium. Bile stasis occur due to obstructed bile dct. And cholangitis and pyogenic abcess are easily complicated. Obstructed and dilated bile duct could often make the retention cyst. The cyst usually contains ova and occasionally adult iorms are aspirated ivithin the cystic fluid. A 53 years-old man with clonorchiasis having retention cvst is reported. The patient I-as admitted to hosptal with epigastralgia and weakness. Nontender, smooth and moderate hard liver was palpated as about 2finger breadth below the right coastal margin. Ova of clonorchis sinensis in stool and skin test for clonorchiasis were positive. L.F.T. were within normal limit. On liver scan with 198 Au colloidal gold on admission, a large single cavity was shown on the posteroin- ferior site of the right lobe. On percutaneous transhepatic cholangiography, nonvisualization of the right hepatic radicle, tapering dilation of the left hepatic radicle with mulberry like cvstic dilatation of small to medium sized bile duct of the left lobe and faint visualization of the common bile duct were shown. Eight adult worm of colonorchis sinensis were aspirated by liver neeedle aspiration. On 30th admission day, first operation was done. 2cm X 3cm sized retention cyst was found on the posteroinferior site of the right lobe with diffuse scattered pyogenic abscesses. Second operation was done I month later the first operation due to obstructed jaundice. Severe dilatation of superficial intrahepatic bile ducts and 2cm X 3cm X 2cm sized hard mass on the bifurcation of the common hepatic duct were found, the latter was histologically confirmed as extrem fibrosis of the wall of bile duct with lymphocytic infiltration without any evidence of malignancy. By operation and biopsy, we confirmed a clonorchiasis with retention cyst and complete obstruc- tion of common hepatic duct due to fibrotic granuloma.