Diabetic foot is categorized into ischemic, neurological and mixed types, with different clinical manifestations, mainly abnormal foot sensation, pain and ulceration. Diabetic foot is a general term for a series of clinical manifestations of the foot caused by peripheral neuropathy and vascular disease in diabetic patients, including foot ulcers, infections or deep tissue destruction. Diabetes mellitus is the leading cause of foot ulceration, infection, ischemia and amputation. The mechanism of occurrence is complex, usually caused by a combination of factors, such as neuropathy, ischemia, foot deformity and foot pressure distribution abnormalities, trauma and inappropriate footwear, etc. The two most important factors are neuropathy and ischemia. 1. Ischemic type: mainly due to ischemia caused by atherosclerosis and obstruction of lower limb arteries, with clinical manifestations such as coldness of lower limb, decrease of skin temperature of foot, intermittent claudication, resting pain, etc., and ulceration and gangrene can occur in serious cases. 2. Neurological type: mainly due to nerve damage caused by neuropathy, clinical manifestations are numbness, pain and other lower limb sensory abnormalities, normal or elevated skin temperature of the foot, walking with a sense of feet on cotton, also can appear ulceration, gangrene. 3. Mixed type: accompanied by lower limb nerve injury and ischemia, clinical manifestations of both ischemic manifestations such as intermittent claudication, and lower limb sensory abnormalities and other manifestations of nerve injury. If the above symptoms occur, it is recommended to consult the doctor in time.