Both diabetes mellitus and hypertension are chronic metabolic diseases. Patients with diabetes mellitus are often combined with hypertension, and patients with hypertension can be combined with diabetes mellitus. Hypertension and diabetes can interact and aggravate each other, and both can produce chronic complications. Having diabetes and hypertension may lead to the following problems: i. Aggravating atherosclerosis and even forming cardiovascular diseases such as coronary heart disease, angina pectoris, myocardial infarction and cerebral infarction. Second, both diabetes and hypertension can affect the fundus of the eye, forming fundus lesions such as fundus hemorrhage or small vein obstruction, affecting the patient’s vision, and in severe cases, retinal detachment. Third, both diabetes and hypertension can affect the kidneys of patients, forming diabetic nephropathy and hypertensive nephropathy, leading to glomerular arteriosclerosis. In severe cases, renal insufficiency or even uremia is formed. Therefore, patients with diabetes combined with hypertension need both good control of blood sugar and good control of blood pressure to delay the complications.