Abstract: OBJECTIVE To evaluate the validity and safety of Dachaihu Granule in treating chronic cholecystitis due to Stagnant Heat in Liver and Gallbladder. METHODS A stratified-block randomized， double-blind， double-dummy， parallel， placebo-controlled trial was designed， with 600 cases with chronic cholecystitis from 8 centers being selected and the ratio of treatment group， placebo group and cholagogic tablet group being 360∶120∶120. Patients in different groups were separately given Dachaihu Granule and cholagogic tablet simulator， Dachaihu Granule simulator and cholagogic tablet simulator， Dachaihu Granule simulator and cholagogic tablet. Then the validity and safety were assessed after 7 days' treatment. RESULTS ①In terms of the comprehensive curative effect of TCM syndromes， it was noticed that there existed no difference between the treatment group and positive medicine group in the integral reduction and disappearance of upper quadrant pain and tenderness， quadrant pain relief evaluated by patients， total symptom scores， integral reduction and disappearance of bitter taste， thirst， constipation and yellow urine， disappearance of vomit， change of gallbladder wall thickness and ultrasonic Murphy's character before and after the treatment， while both the treatment group and positive medicine group were superior to the placebo group(P<0.05~0.01). ②The treatment group and positive medicine group has no difference from the placebo group in integral reduction and disappearance o ffever and nausea integral reduction of vomit， change of gallbladder size and inside diameter of common bile duct. ③Good safety was noticed. CONCLUSION Chronic cholecystitis due to stagnant heat in liver and gallbladder treated by Dachaihu Granule is safe and effective.