The preventive effect of Sosiho-Tang extract administered concurrently with methionine on hepatotoxicity induced by carbon tetrachoride (20% $CCl_4$ in olive oil, 5 ml/kg) in rats was studied. S-GOT values were decreased significantly by the concurrent administration of Sosiho-Tang extract 100 mg/kg with methionine 100 mg/kg and also Sosiho-Tang 200 mg/kg with methionine 100 mg/kg. S-GPT values were decreased remarkably by the concurrent administration of Sosiho-Tang extract 200 mg/kg with methionine 100 mg/kg. In histological observations, the pattern of the contrast group indicated the marked necrosis of the parenchymatous cells around the centrilobular area and the fatty changes of the hepatic cells around the midzonal area, but the concurrent administration of Sosiho-Tang extract 200 mg/kg and methionine 100 mg/kg revealed better improvements than their respective single administration in all pathological aspects.