Yellow nasal mucus is generally staphylococcus aureus infection, which can be seen in rhinitis, sinusitis, nasal foreign body, cold and other diseases, need to be specifically analyzed. 1. Rhinitis: rhinitis is the inflammation of the nasal mucosa and submucosal tissues, rhinitis, nasal mucosa can be manifested as congestion or edema, in addition to the staphylococcus aureus infection, which leads to yellow runny nose. 2. Sinusitis: If the patient has frequent colds or a history of recurrent rhinitis, then the patient may suffer from sinusitis. Staphylococcus aureus is one of the resident bacteria in the nasal cavity, once the patient’s immunity is low, it may cause the occurrence of sinusitis, which leads to yellow nasal discharge. 3. Nasal foreign body: If there is a foreign body in the patient’s nasal cavity, then the patient may be due to nasal irritation caused by staphylococcus aureus attached to cause infection, resulting in staphylococcus aureus in the nasal cavity and nasal mucus mixing, which leads to yellow nasal mucus. 4. Colds: when a cold occurs, the nasal mucosa is stimulated by pathogens, resulting in increased secretions, which may appear yellow in the case of pathogen infection. Yellow nasal mucus may also be caused by other diseases, once the patient found his yellow nasal mucus, need to consult a doctor in a timely manner, under the guidance of the doctor for targeted treatment.