Nose dry, often have dry knot phenomenon, may be due to environmental factors, dry rhinitis and atrophic rhinitis and so on. 1. Environmental factors: the external environment is dry or in the haze, formaldehyde and other harmful gases for a long time in the environment, it is easy to appear nose dry. 2. Dry rhinitis: due to chronic inflammation of the nasal mucosa caused by dry rhinitis, manifested as dry nasal mucosa, congestion, nasal secretion is reduced or covered with thin crusts, so the patient will feel the nose dry often dry knot. 3. Atrophic rhinitis: patients often have abnormal expansion of the nasal cavity, resulting in a decrease in the sensitivity of the nasal cavity nerves, resulting in the illusion of airlessness, resulting in nasal dryness or accompanied by nasal crusts and so on. Appearance of dry nose, often have dry knot phenomenon, may also be other reasons, it is recommended to actively to the regular hospital consultation, clear diagnosis after standardized treatment.