There is no best way to stop mouth breathing. The cause of mouth breathing needs to be found and treated. If it is a habitual behavior, you need to train to change the mouth breathing; if it is due to a disease, such as rhinitis, you need to treat the rhinitis to improve the mouth breathing. If it is a habitual action, you can use the closed-mouth puffing method, such as blowing a trumpet, whistling, etc., to correct the habit of mouth breathing by exercising the upper and lower lip muscles and training the muscles that shut up the mouth. You can also be forced to exercise breathing through the nose to increase the resistance of mouth breathing, such as applying several layers of gauze, wearing a mask when sleeping, etc., the lack of oxygen in the organism is forced to use the nose to breathe to meet the body’s oxygen supply, so as to achieve the improvement of the habit of mouth breathing. If the patient has sinusitis, rhinitis, nasal polyps, nasal turbinate hypertrophy and other diseases, adequate treatment is needed to maintain nasal patency, which can correct the phenomenon of mouth breathing. Generally use hydroxymetazoline hydrochloride nasal drops, furosemide nasal drops, mometasone furoate nasal spray and other drugs, contraction of nasal mucosa and turbinate blood vessels, so that the turbinate shrinkage, relief of nasal congestion, restoration of transnasal respiration, so as to achieve the phenomenon of correcting mouth breathing. In conclusion, if the mouth breathing can not be changed, it is recommended that the patient go to the hospital in time to clarify the cause of the disease for treatment.