Wound healing is essentially tissue damage repair, and many factors are associated with this process, such as blood circulation, nutrient supply, immunity, germ load, fluid balance, etc. The presence of diabetes affects precisely these factors, leading to more complex and difficult wound healing. 1, diabetes leads to vascular neuropathy high blood sugar will interfere with the protein glucose oxidation reaction to produce oxygen radicals, these reactive oxygen species in the body constantly accumulate can not be metabolized, thus triggering oxidative stress to make tissue and cell damage, which leads to microvascular and neurological lesions, the formation of difficult to heal ulcer surface. 2.Diabetes leads to obstructed blood circulation Blood vessels will become narrow, occlusion, damage, etc., resulting in obstructed blood circulation, a large amount of protein, oxygen, vitamins and other substances required for wound repair can not be transported to the wound site, making the repair ability is greatly reduced, and even worsened. 3, diabetes leads to decreased immunity In the environment of high blood sugar, the chemotactic and phagocytic functions of white blood cells are reduced, and the killing power of germs is reduced. In addition, the metabolic function flocculation will also cause a reduction in protein synthesis, and antibodies, interferon are composed of protein, the lack of these substances human response to antigens and immune regulation ability will be reduced. 4, diabetes causes the body fluid balance is disrupted high blood sugar will also cause the extracellular fluid osmotic pressure to rise, water leaks from the cells, while glucose is excreted from the urine, forming osmotic diuresis, resulting in a large amount of water and electrolyte loss through the urine. As dehydration occurs both inside and outside the cells, the fluid balance is disrupted, especially the imbalance of electrolytes at the wound site, which directly affects the healing of injured tissues. 5.Diabetes leads to increased germ load The obstruction of blood circulation leads to the inability of drugs to reach the wound, not to mention the inability to help reduce inflammation in the wound, and the decrease in immunity leads to germ load. In addition, tissue edema, lack of oxygen, sugar-rich environment more conducive to the growth of germs, thus triggering a vicious circle, wound infection more and more serious, and finally gangrene. Diabetic patients should pay more attention to the control of blood sugar after the appearance of wounds, and should be scientifically cautious in the treatment of wounds, if there is necrotic tissue should be removed in a timely manner, topical ointment for antibacterial and anti-inflammatory treatment, if the wound ulcers or does not heal for a long time, we must pay extra attention to the timely treatment of wound repair specialists, do not delay, if the formation of gangrenous wounds may bring physical disability pain.