Objective:To optimize the animal model of liver injury that can properly represent the pathological characteristics of dampness-heat jaundice syndrome of traditional Chinese medicine.Methods:The liver injury in the model rat was induced byα-naphthylisothiocyanate(ANIT) and carbon tetrachloride(CCl_4) respectively,and the effects of Yinchenhao Decoction(茵陈蒿汤,YCHD),a proved effective Chinese medical formula for treating the dampness-heat jaundice syndrome in clinic,on the two liver injury models were evaluated by analyzing the serum level of alanine aminotransferase(ALT),asparate aminotransferase(AST),alkaline phosphatase(ALP), malondialchehyche(MDA),total bilirubin(T-BIL),superoxide dismutase(SOD),glutathione peroxidase(GSH-PX) as well as the ratio of liver weight to body weight.The experimental data were analyzed by principal component analytical method of pattern recognition.Results:The ratio of liver weight to body weight was significantly elevated in the ANIT and CCI_4 groups when compared with that in the normal control(P<0.01).The contents of ALT and T-BIL were significantly higher in the ANIT group than in the normal control(P<0.05,P<0.01),and the levels of AST,ALT and ALP were significantly elevated in CCI_4 group relative to those in the normal control (P<0.01).In the YCHD group,the increase in AST,ALT and ALP levels was significantly reduced(P<0.05, P<0.01),but with no significant increase in serum T-BIL.In the CCI_4 intoxicated group,the MDA content was significantly increased and SOD,GSH-PX activities decreased significantly compared with those in the normal control group,respectively(P<0.01).The increase in MDA induced by CCI_4 was significantly reduced by YCHD (P<0.05).Conclusion:YCHD showed significant effects on preventing liver injury progression induced by CCI_4, and the closest or most suitable animal model for damp-heat jaundice syndrome may be the one induced by CCI_4. Objective: To optimize the animal model of liver injury that can properly represent the pathological characteristics of dampness-heat jaundice syndrome of traditional Chinese medicine. Methods: The liver injury in the model rat was induced by α-naphthylisothiocyanate (ANIT) and carbon tetrachloride (CCl_4 ) respectively, and the effects of Yinchenhao Decoction, a proved effective Chinese medical formula for treating the dampness-heat jaundice syndrome in clinic, on the two liver injury models were based on analyzing the serum level of alanine aminotransferase (ALT), asparate aminotransferase (AST), alkaline phosphatase (ALP), malondialchehyche (MDA), total bilirubin (T-BIL), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) weight to body weight. the experimental data were analyzed by principal component analytical method of pattern recognition. Results: The ratio of liver weight to body weight was significantly elevated in the ANIT and CCI_4 grou Ps when compared with that in the normal control (P <0.01). The contents of ALT and T-BIL were significantly higher in the ANIT group than in the normal control (P <0.05, P <0.01), and the levels of AST , ALT and ALP were significantly elevated in CCI_4 group relative to those in the normal control (P <0.01) .In the YCHD group, the increase in AST, ALT and ALP levels were significantly reduced (P <0.05, P <0.01) but with no significant increase in serum T- BIL. the CCI_4 intoxicated group, the MDA content was significantly increased and SOD, GSH-PX activities decreased significantly compared with those in the normal control group, respectively (P <0.01). in MDA induced by CCI_4 was significantly reduced by YCHD (P <0.05) .Conclusion: YCHD showed significant effects on preventing liver injury progression induced by CCI_4, and the closest or most suitable animal model for damp-heat jaundice syndrome may be the one induced by CCI_4.