Facial paralysis is a paralysis of the facial nerve, which can be categorized into central facial paralysis and peripheral facial paralysis according to the cause of facial paralysis, and both of them will cause the symptoms of shallow nasolabial folds, crooked corners of the mouth, and leakage of wind in speech. Central facial paralysis is an injury to the upper motor neurons, often secondary to stroke, multiple sclerosis and other diseases, with a sudden onset. The symptoms of central facial palsy include shallow nasolabial folds, crooked corners of the mouth, and leaky speech on the side opposite to the lesion. However, the frontal lines are still present, and the patient is able to frown and close his eyes, and he can still show expressions such as crying and laughing, even though he loses his facial movements on the side opposite to the lesion. Peripheral facial paralysis is an injury to the lower motor neurons, often secondary to facial nerve injury, herpes zoster, and other diseases, and will start within one to three days. It may appear on the same side of the lesion with enlarged eye fissures, shallow nasolabial grooves, crooked corners of the mouth, leakage of wind in speech, drooling, and difficulty in performing movements such as frowning, closing the eyes, or whistling, and it may also cause a loss of facial expression on the same side of the face. A small number of patients also experience numbness and pain in the lips and cheeks. Some patients may also experience Bell’s sign, which means that when the eyes are closed with force, the affected side of the eyeball will turn upward and reveal the white sclera. When the above symptoms occur, patients should consult a doctor in time to identify the cause and under the guidance of a professional doctor for treatment and rehabilitation.