Neuropathy is one of the most common complications of diabetes, with a prevalence of 7% to 50%. If various subclinical neuropathies are included, it can be as high as 90%. It is an important cause of disability and death in diabetic patients and seriously threatens the health of diabetic patients. Any part of the nervous system (peripheral nerves, spinal cord and brain) can be affected, and it can occur alone or in combination, among which peripheral neuropathy is the most common. Especially in peripheral neuropathy in the elderly, diabetes is the most common cause of the disease. Peripheral neuropathy refers to the persistent disorder of the axons and supporting tissues of the spinal cord and brainstem lower motor neurons, primary sensory neurons and peripheral autonomic neurons, and various clinical manifestations may occur. Its neuropathology shows Schwann cell edema, axonal degeneration and segmental demyelination.