To establish the molecular mechanism of ginsenoside Rg1 in non-alcoholic fatty liver disease (NAFLD), Sprague Dawley (SD) rats (180-220 g) were randomly divided into a control group, model group, ginsenoside Rg1 low-dose group (30 mg/(kg day)), high-dose (60 mg/(kg day)) group, and simvastatin group (1 mg/(kg day)), with 10 SD rats in each group. The control group was given a normal diet. The model group rats were given high-sugar and high-fat diets for 14 weeks. After the model of NAFLD was established successfully, ginsenoside Rg1 was administered orally for 4 or 8 weeks. The results showed that ginsenoside Rg1 decreased the levels of glucose (GLU), insulin (INS), triglyceride (TG), and total cholesterol (TC) and improved liver function. Meanwhile, ginsenoside Rg1 inhibited the secretion of interleukin-1 (IL-1), IL-6, IL-8, IL-18, and tumor necrosis factor-alpha (TNF-alpha) and improved hepatocyte morphology and lipid accumulation in the liver. Furthermore, ginsenoside Rg1 promoted the expression of peroxisome proliferator-activated receptor-alpha (PPAR-alpha), carnitine palmitoyl transferase 1 alpha (CPT1A), carnitine palmitoyl transferase 2 (CPT2), and cholesterol 7 alpha-hydroxylase (CYP-7A) and inhibited the expression of sterol regulatory element binding proteins-1C (SREBP-1C). In conclusion, ginsenoside Rg1 can inhibit inflammatory reaction, regulate lipid metabolism, and alleviate liver injury in NAFLD model rats.