If the patient’s mouth is crooked and face is half numb, consider the following reasons: 1. Acute onset should be considered to be caused by cerebrovascular disease, such as transient ischemic attack, cerebral infarction or mild cerebral hemorrhage disease. When the cortical brainstem bundle in the patient’s brain is affected, it will cause the patient’s mouth to be crooked and half of the face to be numb, accompanied by the symptoms of tongue extension and obliquity. 2, if the patient’s mouth is crooked and half of the face to be numb with chronic onset, it is considered to be caused by intracranial tumor or intracranial occupancy compressing the patient’s cerebral nerve, which can be clarified by doing head nuclear magnetic head CT examination. 3, if the patient is infected with virus or cold or wind blowing, it will lead to facial nerve paralysis. If the facial nerve paralysis is caused by virus infection or cold or wind, the symptoms of crooked mouth and numbness of half of the face may also appear.