Objective:To investigate the therapeutic effect of total iridoid glycosides of Picrorhiza scrophulariiflora (TIGP) on non-alcoholic steatohepatitis (NASH).Methods:SD rats were fed with high-fat and high-sugar diet for 8 weeks to establish NASH.TIGP were given orally at doses of 20,40 and 80 mg/kg/d for 4 weeks.Triglycerides assay (TG),total cholesterol (TC),low density lipoprotein cholesterol (LDL-C),high-density lipoprotein cholesterol (HDL-C),aspartate aminotransferase (AST),alanine aminotransferase (ALT),fasting plasma glucose (FPG),fasting insulin (FINS),tumor necrosis factor-α (TNF~),interleukin-6 (IL-6),chemokine-1 (MCP-1),leptin (LEP) in serum were tested.TG,TC,superoxide dismutase (SOD),malondialdehyde (MDA),and free fatty acid (FFA) in liver tissue were determined by colorimetric methods.Steatosis of hepatocytes and inflammation was performed by pathological examination.Results:The results showed that TIGP significantly decreased TC,TG and FFA in liver tissue,increased SOD activity,decreased MDA content,decreased serum levels of TG,TC HDL-C/LDL-C,ALT,AST,GLU,HOMA-IR,TNF-α and LEP,and in addition,improved steatosis of liver cells compared to NASH.Conclusion:TIGP had anti-fatty liver effect against NASH rats induced by high-fat and high-sugar diet.Its mechanism was related to the regulation of lipid metabolism and reduction of insulin resistance,through inhibition of oxidative stress and inflammation.