There are many reasons why the tongue suddenly stops moving, mainly craniocerebral diseases, oral diseases and other diseases. 1. Craniocerebral diseases: the main causes of tongue suddenly not moving are craniocerebral diseases, such as concussion, cerebral hemorrhage, epidemic encephalitis B, cerebral contusion and cerebral vascular accidents, etc., which can lead to nerve damage due to craniocerebral injury, thus affecting the tongue and causing the symptom of tongue not moving. 2. Oral diseases: Tongue ulcer and sublingual nerve damage and other oral diseases can also cause sudden immobility of the tongue due to the lesions on the tongue. 3. Other diseases: Other diseases such as neurosis and food poisoning can also cause this symptom. If you have symptoms of tongue movement, it is recommended to seek medical advice.