Objective To analyze the preventive and therapeutic effects of a traditional Chinese medicine Taohe Chengqi decoction on a rat models of hepatic encephalopathy (HE) induced by thioacetamide (TAA).Methods The rat model of HE was established by intraperitoneal injection of TAA,and the effects of Taohe Chengqi decoction were observed by neurobehavioral changes,neurological test,blood ammonia,serum biochemical indexes,and liver and brain pathological examination.Results The rat model of hepatic encephalopathy was successfully established. Low, medium and high dose Taohe Chengqi decoction markedly improved neuro-reflexes and liver and brain pathological damages,and significantly decreased the HE staging and serum biochemical indexes, and the results of high dose group was the best, similar to that of positive drug-treatment group.Conclusions Taohe Chengqi decoction exhibits promising preventive and therapeutic effects on the rat model of TAA-induced hepatic encephalopathy, and these results provide substantial experimetal evidence for its clinical application.