Hand numbness at night when sleeping may be due to local ischemia, acute cerebrovascular disease and other causes, as follows: a. Local ischemia: the most common cause is due to the arm placed under the head for a long time, resulting in pressure on the arm ischemia, such patients will wake up in the morning after the symptoms of hand numbness, through the activity of the affected limb, the symptoms of hand numbness can be gradually relieved. Second, acute cerebrovascular disease: some elderly people sleep at night with hand numbness, is caused by acute cerebrovascular disease, especially cerebral infarction is very easy to appear at night, will lead to a sudden side of the patient’s hand numbness, and can be accompanied by limb weakness. Such patients need to go to neurology for examination and treatment in a timely manner, and the means of examination include head CT, head MRI, cerebrovascular CTA and so on. If the diagnosis of acute cerebral infarction is confirmed, intravenous thrombolysis or endovascular treatment should be given as soon as possible to improve the patient’s symptoms.