This symptom of smelly nasal mucus is mainly considered to be caused by sinusitis, sinusitis when complicated by bacterial infection, especially anaerobic bacteria, it is easy to appear yellowish and smelly nasal mucus; there may also be a foreign body in the nasal cavity, which may cause sinusitis secondary to the infection, and this symptom will also appear. In the treatment, it is necessary to pay attention to the usual blowing of the nose, try to blow the nose clean; there is also for the treatment of infection, mainly for the treatment of bacteria and anaerobic bacteria, you can use cephalosporin antibiotics plus anaerobic bacterial metronidazole for joint application; in addition, the nasal cavity should pay attention to clean, you can use the sea-salt water spray wash and some astringent mucous membrane blood vessels of the drug, such as ephedrine nasal drops or hydroxymetholazoline nasal spray, which can make the nasal cavity more fluent. Can make the nasal cavity more open, so that the nasal drainage is more smooth and clean.