Numbness in the left half of the body from head to toe may be caused by cerebrovascular disease, or may be caused by brain tumors, brain occupancy compression, the specific form of the patient’s morbidity, head MRI examination to clarify: 1, the patient if the sudden appearance of the left half of the body from head to toe numbness, consider acute cerebrovascular disease caused by the site of the lesion easily in the basal ganglia area, the location of the thalamus, easy to appear partial body numbness, such as acute cerebral infarction or cerebral hemorrhage, transient ischemic attack. For example, acute cerebral infarction or cerebral hemorrhage, transient ischemic attack. Patients should immediately consult a hospital to improve the CT, MRI and functional brain imaging examination of the head to clarify the cause of the symptoms. 2, if the patient is gradually appearing, the left half of the body from head to toe numbness, and gradually progressive aggravation, this situation may be caused by brain tumors, occupational compression, through the head CT, head MRI examination can be clarified. The tumor should be treated by surgery or radiotherapy to improve the symptoms.