ObjectiveTo establish an animal model of hepatic encephalopathy (HE). MethodsUsing carbon tetrachloride-alcohol in drinking water to establish a rat model of chronic liver failure-caused hepatic encephalopathy. The behavior activities were observed by maze test, blood biochemistry was measured, and liver and brain morphology was examined by electron microscopy.Results1) Under the naked eyes, the livers of model rats were enlarged in general, their surface was rough, with dark red coarse particles. In the normal group the livers were of normal appearance. There were lots of fibosis, hepatocyte lysis, diffuse necrosis and widespread hepatocyte ballooning degeneration in the model group. 2)Compared with the control group, the model group showed that the escape latency was significantly longer in the Morris water maze test at the ninth week. Took the incubation period extended beyond the normal x +2.5 s as standard, there were 14/20 (55%) rats having a longer latency in Morris water maze test in this experiment. 3) In the HE model group, the blood ammonia concentration was significantly higher than that in the control group,with a significant difference between the two groups (P <0.01). 4) In the normal group ,the EEG was α-wave dominant and without distinct abnormalities, but changes of hepatic encephalopathy appeared in the model group. ConclusionsA rather ideal rat model of liver cirrhosis acompanied with hepatic encephalopathy (HE) has been established. The HE changes can be more easily detected by Morris water maze test in the rats.