The first consideration for the sudden onset of weakness of half of the arms and legs in the elderly is the presence of acute cerebrovascular disease. Such as cerebral infarction, cerebral hemorrhage, etc. Other diseases to be considered are tumor in the brain, subdural hematoma, etc. Therefore, when a patient suddenly develops weakness of one side of the limb, it is recommended to go to the hospital in time to improve the cranial CT or cranial MRI to assist in the diagnosis. After the diagnosis is clear, symptomatic treatment can be carried out. Regardless of which disease is mentioned above, it needs to be treated as soon as possible, if delayed the patient’s symptoms may become more and more serious. Therefore, when there is weakness of limbs, slurred speech, etc., it is recommended to seek medical attention promptly.