Objective To observe the effects of modified Erchen Decocion on the levels of blood lipid, liver fat and serum leptin in rats with non-alcoholic fatty liver disease. Methods 80 SD rats were randomly divided into normal control group, model group, simvastatin group(1.8 mg/kg) and modified Erchen Decoction group(4.5 g/kg), with 20 rats in each group. The normal group were fed with ordinary diet, the other groups were fed with high-fat diet. Gavage was started at the 9th week and lasted for 4 weeks. The weight, liver weight, HE staining, liver function (AST), blood lipids (blood TG, HDL-C, LDL-C), liver lipids(liver TG), serum leptin level were detected. Results At the end of 10 and 12 weeks, pathological results showed that the liver of high-fat diet rats with a typical hepatic steatosis. Biochemical and ELISA results showed, the liver function, blood lipids, liver lipids and serum leptin level in the model group were significantly increased. Compared with model group, the degree of lipid deposition and liver steatosis in modified Erchen Decoction group had obviously improved, and the level of serum leptin was significantly reduced(P<0.05). Conclusion Modified Erchen Decoction could ruduce serum leptin level, lower blood lipids and liver lipids levels. This indicated that modified Erchen Decoction could treat non-alcoholic fatty liver and the mechanism may be related to leptin reducing.