High free fatty acid suggests abnormal lipid metabolism, which can improve the commonly used indicators of lipid metabolism, such as total cholesterol, triglyceride, etc., and active lipid-lowering treatment. Serum free fatty acid is a new biochemical index of lipid metabolism, which is derived from the hydrolysis of total cholesterol or triglyceride by lipase, and can be classified into saturated fatty acid, monounsaturated fatty acid and polyunsaturated fatty acid, and serum free fatty acid measured by enzyme method contains all the above fatty acids. High free fatty acid suggests abnormal lipid metabolism, which is a risk factor for atherosclerosis and insulin resistance. It is recommended to take active lipid-lowering treatment, low-fat diet in life, increase exercise, and use lipid-lowering drugs under the guidance of a doctor if necessary. High free fatty acid should be under the guidance of the doctor to improve the examination and treatment.