Nose always have yellow snot may be related to the acute and chronic inflammation of the nasal cavity and sinuses, common diseases include acute rhinitis, sinusitis and atrophic rhinitis. 1. Acute rhinitis: generally caused by rhinovirus or adenovirus, leading to bilateral turbinate persistent edema, congestion, hypertrophy, secondary bacterial infection, yellow nasal discharge, the patient will have nasal congestion, headache, decreased sense of smell and other related symptoms. 2. Sinusitis: generally manifested as purulent inflammation induced by bacterial infection in the sinuses and nasal cavity, resulting in prolonged yellowish pus nasal discharge, nasal dyspnea, headache and other discomforts; sometimes the pus may flow to the pharynx and larynx, which stimulates the local mucous membranes and causes itchiness, nausea, cough and sputum and other manifestations. 3. Atrophic rhinitis: atrophy of nasal mucosa, glands and bone, odoriferous nasal bacillus infection leads to nasal cavity with yellow snot crust performance. This symptom alone is not enough to diagnose the disease, when the nasal cavity malignant tumor or nasal cavity into the foreign body, may also appear yellow nasal discharge. Therefore, when yellow nasal discharge occurs, the patient should consult a doctor in time to clarify the cause of the disease and take active treatment.