Objective:To investigate the effects of Yinqi Tiaozhi Decoction on lipid metabolism in rats with nonalcoholic fatty liver disease (NAFLD) and the mechanism of action. Methods48 SD rats were randomly assigned into normal group, model group, simvastatin (2.08 mg/kg) group, low-dose (8.28 g/kg), middle-dose (16.56 g/kg) and high-dose (33.12 g/kg) Yinqi Tiaozhi Decoction groups. Except the normal group, high-fat diet was given to rats in the other 5 groups for 12 weeks to establish the NAFLD rat model. After successful modeling, corresponding drugs were administered by gavage to the drug groups, and 0.9% NaCl solution of equal volume was given by gavage to the normal and model groups. At 8 weeks of treatment, wet weight of the liver and liver index were calculated, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), cholesterol (TC) and triglyceride (TG) in serum were detected; the levels of TC, TG, malondialdehyde (MDA), superoxide dismutase (SOD) and free fatty acid (FFA) in liver tissue were determined by ELISA; hematoxylin-eosin (HE) staining and oil red O staining were performed to observe the pathology of liver tissue; and the relative expression of liver X receptor α (LXRα) and sterol regulatory element-binding protein-1c (SREBP-1c) in liver tissue was detected by polymerase chain reaction (PCR).  Results:①Compared to the normal group, the body mass, wet weight of the liver and liver index increased (P<0.05); the levels of ALT, AST, TC and TG in serum increased (P<0.05), the levels of TC, TG, MDA and FFA, the relative expression of LXRα and SREBP-1c mRNA in liver tissue increased (P<0.05) and the SOD level decreased (P<0.05) in the model group. ②Compared to the model group, the body mass, wet weight of the liver and liver index decreased (P<0.05); the levels of ALT, AST, TC and TG in serum decreased (P<0.05), the levels of TC, TG, MDA and FFA and the relative expression of LXRα and SREBP-1c mRNA in liver tissue decreased (P<0.05) and the SOD level increased (P<0.05) in the simvastatin group and Yinqi Tiaozhi Decoction groups. ③Compared to the simvastatin group, the levels of ALT and AST in serum decreased in the middle-dose and high-dose Yinqi Tiaozhi Decoction groups (P<0.05), the body mass, wet weight of the liver and liver index decreased, the levels of FFA and MDA and the relative expression of LXRα mRNA and SREBP-1c mRNA decreased (P<0.05), and the SOD level increased (P<0.05) in the high-dose Yinqi Tiaozhi Decoction group. ④The body mass, wet weight of the liver and liver index decreased significantly in the high-dose group compared to the low-dose group (P<0.05); the levels of ALT and AST in serum decreased in the middle-dose group compared to the low-dose group (P<0.05), and the levels of ALT, AST, TC and TG decreased in the high-dose group compared to the low-dose group (P<0.05). The levels of TC and TG (middle-dose group vs. low-dose group) and of FFA, MDA and SOD (high-dose group vs. low- and middle-dose groups) decreased significantly with increase in dose; and the relative expression of LXRα mRNA and SREBP-1c mRNA in liver tissue decreased in the high-dose group compared to the low-dose group (P<0.05).  Conclusion:Yinqi Tiaozhi Decoction reduces significantly the levels of blood and liver lipid in in rats with NAFLD, inhibits lipid accumulation, reduces oxidative stress, protects liver function, and improves pathological injury of the liver. The mechanism of action may be related with inhibition of the expression of LXRα and SREBP-1c.