The nasal congestion at night may be caused by inflammatory infectious nasal cavity, sinus, and allergic disease factors, as follows: 1. Patients often have chronic rhinitis, sinusitis, allergic rhinitis, etc., which leads to chronic congestion, swelling or edema of the nasal mucosa, resulting in nasal congestion, especially at night when the body is lying flat, the congestion and swelling of the nasal mucosa will be further aggravated, resulting in nasal congestion. 2, some patients may have obvious deviation of the nasal septum, and even further polyps, papillomas and adenoid hypertrophy in the nasal tract, if necessary, further detailed examination is needed to help clarify the diagnosis.