Non-alcoholic fatty liver disease is a clinicopathological syndrome characterized by diffuse hepatocellular steatosis, including simple fatty liver and especially evolving steatohepatitis and cirrhosis, which is closely related to insulin resistance and genetic susceptibility to its development, except for alcohol and other definite hepatodamaging factors. With the increasing incidence of obesity and diabetes, non-alcoholic fatty liver disease has now become one of the common chronic liver diseases in China, seriously endangering people’s health. Clinical diagnostic criteria: non-alcoholic fatty liver disease can be diagnosed if any of the following items 1~5 and item 6 or 7 are present (1) No history of alcohol consumption or alcohol consumption equivalent to <140g of ethanol per week for men and <70g per week for women; (2) Excluding viral hepatitis, drug-related liver disease, total parenteral nutrition, hepatic sinusoidal degeneration and other specific diseases that can lead to fatty liver; (3) In addition to the clinical manifestations of the primary disease, there may be non-specific symptoms and signs such as malaise, dyspepsia, vague pain in the liver area and hepatosplenomegaly; (4) There may be overweight (5) Serum transaminase and glutamyl transpeptidase levels may be mildly to moderately increased (less than 5 times the upper limit of normal value), usually dominated by increased glutamyl aminotransferase; (6) Liver imaging manifestations meet the diagnostic imaging criteria for diffuse fatty liver; (7) Histological changes on liver biopsy are consistent with pathological diagnostic criteria of fatty liver disease.