Definition: Fatty liver is excessive fat content in the liver, which is a common disease with a prevalence of 5% in our population. With the improvement of people’s living standard and the change of diet structure, the incidence of fatty liver has a tendency to increase. Etiology: There are many factors that cause fatty liver, such as chronic alcoholism, nutritional deficiency or overnutrition, hyperlipidemia, diabetes, endocrine disorders, etc., which can cause fatty liver, especially related to elevated blood lipid and blood sugar levels. The incidence of fatty liver increases with age, and increases significantly after menopause in women. Most patients with fatty liver have no conscious symptoms, but a few may experience pressure or fullness in the liver area, accompanied by fatigue, abdominal distension, etc. In severe cases, patients may feel pain in the liver area, nausea and vomiting, and mild jaundice. Physical examination may reveal hepatomegaly, and laboratory tests may show increased blood cholesterol and triglycerides and increased transaminases. Diagnosis: Diagnosis of fatty liver is generally based on medical history, etiology, hepatomegaly, high blood lipids, and ultrasound findings of dense microscopic waves in the liver, etc. Confirmation of diagnosis requires biopsy by liver aspiration. Although most patients with fatty liver have no conscious symptoms and are only detected during physical examinations, the dangers of fatty liver cannot be ignored. The incidence of fatty liver fibrosis is reported to be 25%, and about 1.5-8% of patients can develop cirrhosis, and alcoholic fatty liver can lead to sudden death.