When the nasal mucus is greenish, the patient is considered to have rhinitis or sinusitis. In sinusitis, after the infection in the sinus, there can be greenish purulent discharge, nasal congestion, headache, and even loss of smell and other symptoms. As sinus infection can be combined with anaerobic bacterial infection, the nasal discharge is yellowish-green and can be accompanied by some unpleasant odor, and the patient needs to go to the hospital for examination and clear diagnosis through nasal endoscopy and sinus CT when such symptoms appear. If the diagnosis of sinusitis is made, the patient needs anti-inflammatory treatment, and it is recommended to use broad-spectrum antibiotics, as well as medication to promote the dilution of secretions and nasal decongestant nasal drops for treatment. If sinusitis is repeatedly infected and conservative treatment does not work well, surgery is required.