Clear blisters in the mouth may be caused by physiological factors, but also may be related to mucous gland cysts, pemphigus and other factors. 1. Physiological factors: If the food is too hot in the process of eating, the mucous membrane of the tongue and the mucous membrane of the side wall of the mouth will be damaged, thus appearing in the mouth to grow a transparent blisters symptoms. Usually do not need special treatment, you can use the gargle for gargling, drink a lot of water and pay attention to oral hygiene, after a period of time can disappear by itself. 2. Mucous gland cysts: usually due to duct trauma, rupture, mucus leakage or ductal system disorders, resulting in cystic lesions of the salivary glands, usually appear in the mouth of transparent blisters. Can be in the doctor’s guidance for surgical resection treatment, in the postoperative need to pay attention to local care work, to avoid infection. 3. Pemphigus: mainly due to the immune system disorders, thus causing the skin or mucous membrane flaccid blisters, vesicles and other lesions, thus causing the mouth to grow transparent small blisters. Usually you can choose glucocorticosteroids, cyclosporine and other drugs as prescribed by the doctor. If the symptoms of clear blisters in the mouth, it is recommended to consult the stomatology department in a timely manner, under the guidance of the doctor to clarify the cause of the treatment.