The main reason for babies to sleep with their mouths open and snoring is narrow airway, especially adenoid hypertrophy, swollen tonsils, allergic rhinitis, enlarged turbinates or deviated septum that cause poor nasal ventilation, which will lead to open mouth breathing or snoring. In addition, there are children with narrow airways due to obesity, and some children with small jaws, which are small because the jaws can retract, can lead to snoring and open-mouth breathing. When sleeping, the root of the tongue falls back and blocks the airway, and in severe cases, it may even cause apnea and lack of oxygen to the brain, leading to easy fatigue, memory and inability to concentrate and other decline in the child’s ability. Breathing through the mouth will also cause excessive protrusion of the maxillary front teeth or upper lip is too short, the lips can not be naturally closed, open lips and teeth do not look good and affect the aesthetics, breathing through the mouth to take away the moisture in the oral cavity caused by a dry mouth, pharyngeal discomfort, the mucous membranes in the oral cavity, the gums lack of saliva moisturizing and cleaning, gingivitis can easily be caused. From this we can see that do not underestimate the sleep snoring and open-mouth breathing, long-term harm is not small, if you sleep every day, you should go to the hospital to do a checkup by a professional physician to give a solution.