Objective: To investigate the correlation between different levels of fractional exhaled nitric oxide (FeNO) and inflammatory phenotypes in patients with chronic obstructive pulmonary disease (COPD). Methods: A total of 153 COPD patients admitted to the department of respiratory of Beijing Luhe Hospital Affiliated to Capital Medical University in Beijing Tongzhou district from January 2016 to June 2018 were selected as the study subjects. All patients improved FeNO level detection, lung function detection, serum inflammatory reaction markers detection and induced sputum test. The relationship between FeNO level and clinical features and inflammatory phenotypes of COPD was analyzed. Results: With the increase of FeNO level, the lung function decreased, dyspnea symptoms increased, and inflammatory response indicators increased of COPD patients (P<0.05). The inflammatory phenotypes of COPD at different FeNO levels was statistically significant (P<0.05). FeNO levels in eosinophilic COPD patients were higher than those in non-eosinophilic COPD patients[(35.61±7.18) ppb vs (23.47±3.02) ppb, P<0.05]. FeNO was positively correlated with eosinophil count and inflammatory factor levels (P<0.05), and negatively correlated with lung function (P<0.05). Conclusion: FeNO level is high in eosinophilic granulocyte COPD patients in Beijing. FeNO is a sensitive indicator of airway inflammation in COPD.