Objective:To investigate effects of the method for regulating qi to dissipate phlegm and blood stasis on plasma tissue-type plasminogen activator（t-PA） and plasminogen activator inhibitor（PAI-1） in non-alcoholic steatohepatitis（NASH） rats

and to explore the prevention and treatment mechanism of NASH.Methods:NASH model rat was induced by 12-week high fat diet

and different doses of Chinese herbs for regulating qi to dissipate phlegm and blood stasis were given to prevent and treat NASH.Plasma t-PA and PAI-1 were detected with chromophorous substrate assay

and the pathological changes of the liver were observed with optical microscope.Results:The liver tissue of NASH rats showed severe steatosis

and different degrees of inflammation

cell infiltration

necrosis of hepatocytes and exudation in the portal area as compared with the normal rats;Plasma PAI-1 activity and the ratio of PAI-1/t-PA in the model group were significantly increased.Chinese herbs could improve the steatosis of hepatocytes and inflammatory activity

and significantly decrease the levels of plasma PAI-1 activity and the ratio of PAI-1/t-PA.Conclusion:PAI-1 possibly participates in the generation and development of NASH induced by high fat diet

and Chinese herbs for regulating qi to dissipate phlegm and blood stasis can significantly regulate the secretion of PAI-1

and the balance of the fibrinolytic system

and can prevent further development of NASH.