When young hamsters were fed on a diet containing casein, sugar, fat, cellulose, cholic acid and cholesterol for two months, most animals developed gallstone, The authors used this animal model to observe the effect of Clematis Chinensis Osbeck(Radix Clamatidis)on gallstone prevention. Twelve or thirteen hamsters were administered intragastrically with Clematis Chinensis Osbeck 1 g/d or 0.6 g/d for 2 months,gallstone was found in 8.3%and 7.7% of them respectively,significantly lower than that of the control group(n=15, 53.3%),but similar to that of the ursodesoxycholic acid group(n=14,7.1%).