Hepatic encephalopathy is caused by disorders affecting the liver. The exact cause of the disorder is unknown. It occurs changes in mental state, consciousness, behavior, personality and changes in mood include forgetfulness, confusion, disorientation, delirium, dementia, decreased alertness, daytime sleepiness, decreased responsiveness, progressive stupor, coma. As 3 admission patients into oriental hospital of daejeon university include 2 cases of cerebral infarction, 1 case of liver cirrhosis, we found those are all hepatic encephalopathy. But until the diagnosis is made, we have many mistakes to find correct. Among the mistackes, specialy mixed thing is to compare hepatic encephalopathy and cerebral infarction. So, we report these cases with a brief review of related literatures.