There are more reasons for poor nose breathing, such as allergic rhinitis, deviated nasal septum, hypertrophy of nasal turbinates and so on. 1. Allergic rhinitis: belongs to a kind of chronic reactive inflammatory disease of nasal mucosa, belongs to a type of allergic reaction. It can lead to nasal itching, paroxysmal continuous sneezing, a large amount of watery nasal discharge, nasal congestion and other uncomfortable symptoms. 2. Deviated nasal septum: It refers to the deviation of nasal septum to one side or both sides or localized protrusion, which leads to the appearance of nasal cavity dysfunction. Such as nasal congestion, headache, nosebleed, etc. This disease is mainly caused by uneven development of nasal septum, trauma, occupational disease. 3. Nasal turbinate hypertrophy: it means that the nasal mucosa is stimulated by long-term inflammation, which leads to edema and congestion of local tissues, hyperplasia and hypertrophy, polypoid lesions. It can lead to persistent nasal obstruction, olfactory impairment, dizziness and other uncomfortable symptoms. In addition, colds, nasal polyps, sinusitis, nasal tumors, etc., can lead to nasal congestion, thus causing the nose to breathe poorly, to the hospital in a timely manner, to identify and diagnose.