Unilateral nostril runny nose, consider nasal foreign body or unilateral sinusitis, etc., need to do nasal endoscopy, if necessary, combined with sinus CT examination to clarify the diagnosis, according to the specific disease standardized treatment. 1. Nasal foreign body: rarely seen in adults, mostly seen in children, there are various kinds of foreign bodies can be rubber, peanuts, beans, metal and so on. The common symptom is unilateral runny nose, the beginning can be clear nasal discharge, if the foreign body stays longer to stimulate the nasal mucosa will have nasal congestion, thick nasal discharge or even with blood in the snot odor. After the discovery of the foreign body will be removed, according to the inflammation of the nasal cavity, nasal irrigation and anti-inflammatory treatment. 2. Unilateral sinusitis: runny nose in unilateral nasal cavity, the beginning can be clear nasal discharge, with the development of the disease can have bilateral flow of mucopurulent nasal discharge combined with nasal congestion, headache. However, there are some patients who have unilateral nasal cavity in this situation. At this time, we need to do nasal endoscopy to see the nasal mucosa, do sinus ct to see the degree of sinus lesions and then treatment. Available nasal glucocorticoid spray, such as: budesonide nasal spray; mucus drainage agent to promote secretion discharge, such as: eucalyptus-pinocampus enteric soft capsule; leukotriene receptor antagonist to reduce the inflammatory response, such as: montelukast sodium and so on. When standardized conservative treatment is ineffective, surgical treatment can be performed after perfect evaluation, such as: nasal endoscopic sinus opening. If there is a unilateral nostril runny nose, you need to go to the hospital in time, clear diagnosis and follow the doctor’s instructions for targeted medication and treatment.