The main differences between type 1 diabetes and type 2 diabetes are the differences in etiology, clinical symptoms, diagnosis and treatment. The first is the difference in etiology. Type 1 diabetes has a genetic defect that prevents it from producing enough insulin on its own, and the lack of insulin prevents the cells from storing excess blood sugar, resulting in hyperglycemia. Type 2 diabetes is an acquired insulin resistance, in which insulin secretion is normal or even increases at the beginning, but the insulin receptors do not work properly, and the cells cannot respond to insulin and store excess blood sugar, resulting in hyperglycemia. This results in hyperglycemia. The difference between the clinical manifestations is that type 1 diabetes mostly has severe hyperglycemia, the symptoms of three more and one less are more typical, and often the serious complication of diabetes, diabetic ketoacidosis, can occur spontaneously, and blood glucose fluctuates more. In contrast, type 2 diabetes has obvious symptoms of weakness and thirst when hyperglycemia is present, but weight loss is often not obvious and often combined with obesity, and vascular and neurological complications can often occur before a clear diagnosis is made. The difference in diagnosis is that the onset of type 1 diabetes is young, mostly less than 30 years old, with sudden onset, obvious symptoms of triglycerides and elevated blood glucose, low levels of insulin and C-peptide can be found in blood tests, and insulin-related antibody tests are mostly positive. On the other hand, type 2 diabetes is common in middle-aged and elderly people, and it is common in obese people, often combined with abnormal blood pressure and blood lipids, with insidious onset and no obvious symptoms in the early stage. Blood tests for insulin and C-peptide levels are normal or increased, and in the late stage, they decrease. Antibody tests related to insulin are mostly negative. Finally, there is a difference in treatment. Type 1 diabetes is not treated with oral hypoglycemic drugs and needs to rely on insulin treatment for life. While type 2 diabetes can be treated without relying on insulin in the early stage, diet, exercise and medication are effective, and insulin treatment is also needed when the islet function is completely depleted or when serious acute and chronic complications occur. Therefore, there is a difference between type 1 diabetes and type 2 diabetes, and the type of diabetes needs to be clarified after the blood glucose is clearly elevated in order to choose the correct and reasonable method to lower sugar.