Hypertension is one of the common concomitant diseases of diabetes mellitus, and the high prevalence of hypertension among diabetic patients is due to the following reasons: i. Hypertension and diabetes mellitus are both metabolic diseases with a common pathogenetic basis, such as obesity, insulin resistance, and sedentary and less-active lifestyles, which can cause hypertension as well as diabetes mellitus. Second, long-term diabetes can aggravate the development of atherosclerosis, and atherosclerosis can cause or aggravate hypertension. Third, diabetes can lead to an inflammatory response in the blood vessels, activating the body’s RAS system thereby affecting blood pressure. Fourth, when atherosclerosis in diabetic patients involves renal blood vessels, it can cause renal artery stenosis or complicate diabetic nephropathy and renal insufficiency, and hypertension can occur. So long time poor control of diabetic patients, can cause hypertension.