Diabetes is a common chronic disease and a lifelong disease. The danger of diabetes lies in its complications, and diabetic foot is the so-called diabetic foot rot, which is one of the most serious complications of diabetes, and its early signs are mainly in the change of foot sensation and skin color. Because the diabetic foot is the joint cause of lower limb vascular and neurological lesions, the early stage can appear vascular inaccessibility or even occlusion of the lower limbs, resulting in swelling and ischemia of the foot, darkening of the skin color, purple and gray, drying of the skin, dry flaking and even cracking of the foot. Abnormal sensation may include numbness and pins-and-needles pain. When the sensation is reduced, there can be walking like stepping on cotton, soft, deep one foot, shallow one foot, unstable walking. Because of ischemia and hypoxia, cold feet can also appear, and because of the loss of sensation, the pain and temperature sensation are reduced, when encountered with heat and pinprick will appear foot rot, because the blood vessels are not smooth, poor blood supply, there will be a long-lasting wound or even ulcers, gangrene, and rapid spread. Therefore, the early signs of diabetic foot rot are mainly abnormal pain and sensation, change of skin color and long-lasting ulcers.