Objectives : Cirsii Japonici Herba (CJH) is one of medicinal plants that has been frequently used for styptic purposes in Asian countries. In order to evaluate a hepatoprotective effects of CJH in the liver fibrotic diseases, the present study investigated how CJH improves a hepatic function in the dimethylnitrosamine(DMN) treated rat. Methods : CJH were orally administered to rats that has been treated with DMN. Subsequently, the amount of blood L-asparate aminotransferase (AST), L-alanine aminotransferase (ALT), and hydroxyproline were quantitated. Several histopathological markers for examining the degree of hepatic fibrosis were investigated by H-E and Masson-Trichrome staining. Results: DMN treatment caused a increase of relative liver weight to the body at 14 days after DMN induction, Administration of CJH with 100mg/kg and 1,000mg/kg dose decreased significantly the AST level elevated by DMN injection(p<0.01). But ALT level was not improved. The hydroxyproline level was reduced by a simultaneous treatment of CJH with DMN for 7 days, but not recovered completely to its normal value, CJH administration improved conspicuously the DMN-induced histopathological changes of liver such as granuloma, but cell necrosis and fibrosis were not improved with CJH 1,000mg/kg dose. Conclusion: These results indicate that CJH has protective effect on liver injury and can inhibit liver fibrosis Induced by DMN in rats.