The authors studies 3 cases of Clonorchis sinensis by computed tomography and the operative findings were compared with the preoperative findings of CT scan. Of 3 cases, 2 cases showed moderate degree dilation of gall bladder with thickening of its wall and moderate or minimal degree dilation of common bile duct and intrahepatic biliary trees in CT scan. The remaining 1 case showed moderate degree dilatation of gall bladder with markedly dilated intrahepatic biliary trees. We found that the opertive findings were well corelated with the preoperative findings of CT scan. It is our belief that the CT scan in clonorchis sinensis is the most eraliest and reliable mean for determination of surgical therapy.