A 58-year-old male liver cirrhosis patient, who had a history of recurrent hepatic encephalopathy, was admitted to our hospital because of clouding of consciousness. He had an episode of recent head trauma. On admission, he was drowsy and exhibited flapping tremor, fetor hepaticus and ascites. Laboratory data showed an increase in blood ammonia level, and a decrease in peripheral thrombocytes, serum albumin and prothrombin value. A ratio of branched-chain to aromatic amino acids was reduced. Antibody against hepatitis C virus was positive. His electroencephalogram showed bilaterally large synchronous slow waves. He was treated with intravenous branched-chain amino acids, and recovered. Cranial computed tomography on day 9 demonstrated a crescent shaped area of low density in the right frontotempoparietal subdural region. He was diagnosed as chronic subdural hematoma, which was treated surgically. It has been suggested that chronic subdural hematomas develop as a complication of hemostatic deficiency due to liver cirrhosis.