Diabetes mellitus (DM) is a common endocrine metabolic disease, a group of chronic, systemic metabolic diseases characterized by hyperglycemia caused by defective insulin secretion and/or its reduced biological effect (insulin resistance). Chronic hyperglycemia will lead to multiple tissues in the body, especially eye, heart, blood vessel, kidney and nerve damage or organ insufficiency or failure, resulting in disability or death. With the change of people’s lifestyle and the acceleration of the aging process of the population, the prevalence of diabetes in China is on the rise, becoming the third important chronic non-communicable disease that seriously endangers people’s health after cardiovascular diseases and tumors. 1, the high prevalence of diabetes, chronic complications are common, has become a major social problem threatening people’s health. In 1999, WHO divided diabetes into four types: type 1 diabetes, type 2 diabetes, special type of diabetes and gestational diabetes. 3. The typical symptoms of diabetes are often “three more and one less”, i.e. polyuria, polyphagia, polyphagia and lethargy. However, more than 50% of patients with type 2 diabetes can have no symptoms or only some of the symptoms of complications, and the onset is insidious. 4, urine sugar is an important clue to diagnose diabetes, but not a diagnostic criterion. The diagnosis of diabetes is based on venous plasma glucose, fasting blood glucose (FPG) ≥ 7.0mmol/l (126mg/dl), 2 hours after meal glucose ≥ 11.1mmol/l (200ng/dl). 5.Diabetes chronic complications mainly include: macroangiopathy, microangiopathy, neuropathy, eye complications and other lesions. 6, WHO recommends that diabetes treatment includes five aspects: diet, exercise, medication, blood glucose monitoring and patient education. Regardless of the type of diabetes, insulin therapy is the best choice, and diabetics should not be afraid of insulin.