Lip trembling is seen in the following diseases: First, if a patient with cerebral infarction, especially a patient with lobe infarction, has mouth trembling, involuntary twitching, and pouting, smacking his lips incessantly, this phenomenon may be a seizure, and an EEG can be done to clarify whether there are epileptic waves. The second is the trembling of the lips. For example, if a female patient does not have hypertension or diabetes, the trembling of the mouth, especially after emotional excitement, may be related to mental factors. Third, the appearance of lip tremors, accompanied by tremors of the limbs, such as resting tremors of the hands, walking slowly, unsteadily, and leaning forward. In elderly patients, it is important to consider that the patient may have Parkinson’s disease, and a cranial magnetic resonance examination can be done at the hospital at this time. In younger patients with a family history of lip tremors and tremors in the hands, idiopathic tremor may be present.