An experimental study was done on rabbits to observe the effects of several anticlonorchial drugs on the pathology of the liver infested with Clonorchis sinensis. After two months of infestation with Clonorchis sinensis by giving 400 ~ 500 metacercariae by mouth, hexachlorophene, chloroquine 2,2 methylenebis (3,4,6 trichlorophenoxy acetic acid) and Hetol were administered orally and follow up macro-and microscopic studies of the liver pathology were done in 2 to 3 days, one month, 2 months and 3 months after the completion of medications. The results obtained in this study are as follows: 1. In both groups which were administered hexachlorophene piperazine 20mg/kg for seven days or 8mg/kg for 18 days, the macroscopic findings of the liver after 3 months revealed only minimal changes of the color and consistency The histopathological findings were the reduction of fibrosis, pseudolobulation, proliferation and adenomatous hyperplasia of bile ducts, and regeneration of liver parenchyma. 2. In groups which were administered chloroquine phosphate 20mg/kg for 18 days or 40mg/kg for 5 days, and also in groups which were administered dithiazanine iodide 30mg/kg for 18 days or 60mg/kg for 5 days, no significant findings of recovery were observed either macroscopically or microscopically. 3. In the group which was given 20mg/kg of 2,2 methylenebis(3,4,6 trichlorophenoxy acetic acid) for 5 days, prominent healing of the damaged tissues was observed after 2 months, revealing the decrease of fibrous tissue, caliber of bile ducts and adenomatous hyperplasia of the epitherial cells of the bile ducts, and regenerationof liver parenchyma. 4. In the group which was given Hetol 200mg/kg for 5 days, swelling, congestion and eddish-brown discoloration of the liver were noted macroscopically after 3 days of completion of drug administration. Hemorrhage, congestion, necrosis and degeneration of the parenchyma were observed microscopically After 10 days, liver appeared almost normal macroscopically, but marked fat degeneration was noted microscopically. After 2 months, the liver was almost normal in gross appearence with only slight atrophy and also marked healing was observed microscopically, i. e. decrease of fibrous tissue and reduction of the previously enlarged bile duct and the regeneration of the liver parenchyma.