Numbness in the left foot and left hand may be due to cerebrovascular disease, intracranial occupying disease, peripheral neuropathy and so on, as follows: First, cerebrovascular disease: If the patient is suddenly symptomatic, consider the possibility of cerebrovascular disease, which can be clinically seen in ischemic cerebrovascular disease, cerebral infarction or transient ischemic attack, and also in hemorrhagic disease, such as cerebral hemorrhage. Generally, after CT or MRI examination of the head, the lesion can be diagnosed. Numbness of the left hand and left foot is mostly seen in lesions of the thalamus. Second, intracranial occupational disease: If the slow aggravation of the gradual appearance of the clinical can appear intracranial occupational disease, mostly seen in the thalamus or cerebral bridge lesions, the patient can appear numbness, after the head CT or nuclear magnetic examination can confirm the diagnosis. Third, peripheral neuropathy: numbness of the left hand and foot can be clinically seen in peripheral neuropathy, mostly due to the left hand and foot being stuck, or poor local blood circulation, and the diagnosis can be confirmed by electromyography. Fourth, the cervical spine and lumbar spine lesions: can be due to the cervical spine and lumbar spine lesions at the same time, resulting in the patient appeared numbness of the left hand and left foot.