Diabetic foot is a diabetic patient’s lesion aggravation caused by peripheral nerve and peripheral vascular lesions, the lower limb local skin resistance is weak and lead to lower limb infection, ulcer formation and deep tissue destruction. Due to long-term stimulation by high blood sugar, lower limb blood vessel sclerosis, thickening of blood vessel wall, poor elasticity, easy to form thrombus in the blood vessel, so that lower limb blood vessel occlusion, peripheral nerves are damaged, resulting in lower limb tissue lesions, because toes are farthest away from the heart, blood circulation is the worst, the phenomenon of blood vessel occlusion is the most serious, and the skin is very easy to ischemia, purple, oedema, black, rot and necrosis, and formation of gangrenous ulcers. If the patient does not consult the doctor in time, or the treatment method is inappropriate, the aggravation of the infected ulcer will lead to sepsis, affecting the function of the heart, and the patient’s life is in danger, in order to save the life, the patient has no choice but to need amputation treatment. After amputation, if the local infection and blood glucose control is not good, the wound may heal poorly and need to be amputated again. Therefore, timely attention and control of diabetic foot is very important. The patient was 70 years old, suffering from lung cancer, hypertension, coronary heart disease and diabetes mellitus, and his diabetic foot was severely infected and gangrenous. The patient had been to several first-class tertiary hospitals in Beijing, all of which recommended amputation after evaluation of his condition. The patient had suffered from chills, fever and shock due to foot ulcer infection. The patient was admitted to the hospital and found that the dorsalis pedis arterial pulsation of the right lower limb had almost disappeared, and most of the skin of the foot was ischemic necrosis with ischemic necrosis of the fourth and fifth toes, and a large amount of pusy and bloody grayish-white malodorous liquid was overflowing, which was so foul that people could almost be suffocated by fainting and asphyxiation. Routine blood tests showed severe systemic infection. Treatment was firstly given to debride the necrotic tissues of the foot, and at the same time, systemic anti-infective treatment and unblocking of peripheral vasculature were carried out. Initial treatment controlled the systemic infection, and the dorsalis pedis artery could be palpated, and the local infectious exudate was reduced. Further for foot ulcers precise debridement was performed using nibbling. During the treatment of infection control, the local exudate culture showed methicillin-resistant Staphylococcus aureus infection (MRSA) for several times, therefore, the patient was isolated and monitored, and gauze wound dressing was used for multiple dressing changes, negative pressure suction and skin grafting, etc. Meanwhile, the blood pressure and blood glucose level were strictly controlled, and coronary artery disease was treated to protect the cardiac function, so the local infection was finally controlled after three months, and the culture of exudate of ulcerated wound was performed. The exudate culture of the ulcer wound showed no bacterial growth, the granulation tissue and plantar skin regenerated, and the infected wound gradually shrunk and healed. The patient was discharged from the hospital with a normal walking condition. The prominent difficulty in the treatment of this patient was the persistent foot infection, especially the emergence of methicillin-resistant Staphylococcus aureus infection, which caused local tissue and skin necrosis and delayed wound healing. The key to control the infection is to change the medication several times to remove the infected lesion, do the culture of secretion before each medication change, and choose the sensitive drug treatment according to the culture result. In the treatment of diabetic foot, the key point is to integrate the patient’s systemic health status and psychological factors, to control infection and stabilize blood glucose as the core, to formulate individualized and precise treatment plan, and to use the combination of traditional Chinese and Western medicine, internal medicine and minimally invasive surgery. We pay attention to every detail of wound dressing change, summarizing and adjusting the type, dosage and timing of the medication according to the wound granulation and skin condition, so as to ensure that the ulcerated wound heals as soon as possible.