Numbness of half of the body may be caused by physiological, intracranial lesions, cervical spine lesions and other reasons. 1. Physiological: it may be due to the body resting in side-lying position for a long time, which leads to localized pressure, resulting in ischemic numbness, and thus the phenomenon of half body numbness. 2. Intracranial lesions: such as cerebral hemorrhage, cerebral thrombosis and cerebral embolism. They may cause numbness of half of the body, accompanied by dizziness, headache, nausea, vomiting, motor dysfunction and other symptoms. 3. Cervical spondylosis: In the case of cervical spondylosis, it can cause damage to the spinal cord, resulting in half of the body numbness symptoms. In severe cases, the symptoms can be combined with sensory impairment, abnormal urination and defecation, and other clinical symptoms. It is recommended that patients with numbness on one side of the body should go to the hospital in time to take effective treatment after eliminating physiological causes.