Children sleeping with their mouths open is not necessarily adenoid hypertrophy, if only a mild open mouth may be a normal phenomenon, it may also be the inferior turbinate hypertrophy, nasal septum deviation and other diseases. 1. Physiological factors: healthy children sometimes sleep with their mouths open, mild open-mouth breathing is a normal phenomenon, then if the child’s mouth gently closed, the child can often be naturally converted to breathe through the nasal cavity. 2. Adenoid hypertrophy: adenoid hypertrophy can lead to open-mouthed sleep symptoms, this is due to the hypertrophy of the adenoids blocking the posterior nostrils, part of the child with age, adenoids gradually shrink, can be relieved on their own, if the symptoms are serious surgical treatment. 3. Enlarged inferior turbinate: Enlarged inferior turbinate can also lead to the symptom of sleeping with the mouth open, which is caused by the enlarged inferior turbinate blocking the nasal cavity, and can be treated through interventional surgery and other ways. 4. Deviated septum: A deviated septum can also lead to open-mouthed sleep, and children may experience alternating nasal congestion, which can be treated with surgery. If the patient sleeps with his mouth open, there are other possibilities, such as narrowing of the posterior nasal passage, etc., it is recommended to consult the ENT clinic in a timely manner to find out the cause of the problem and follow the doctor’s instructions for disposal.