Objective To observe the correlation between the exhaled nitric oxide（FeNO） and syndrome differentiation of traditional Chinese medicine（TCM） in patients with bronchial asthma， and to guide clinical differentiation of TCM. Methods 94 patients with bronchial asthma were divided into two groups according to TCM syndrome differentiation type： Cold Asthma Syndrome， Hot Asthma Syndrome， Wind Asthma Syndrome， Phlegm Asthma Syndrome and Pulmonary and Kidney Deficiency Syndrome， and compared the detected FeNO Type of FeNO， and explore the correlation between the two. Results The average number of FeNO points in wind-asthmatic syndrome and cold-stagnation syndrome was significantly higher than that in sputum-asthenia syndrome， heat-asthmatic syndrome and lung-kidney deficiency syndrome（P<0.05）. There was no significant difference between the two groups（P>0.05）. There was no significant difference between the two groups（P>0.05）. Conclusion The study suggests that the exhaled nitric oxide in asthmatic syndrome type from high to low， followed by wind-induced asthma， cold asthma， phlegm， lung deficiency syndrome and heat syndrome.