Objective:To observe the efficacy and safety of azithromycin combined with Bailing capsules in the treatment of chron -ic obstructive pulmonary disease ( COPD) in stable phase .Methods:Totally 154 cases of COPD patients were randomly divided into the treatment group(80 cases)and the control group(74 cases).Both groups were treated with the routine symptomatic treatment , and at the same time, the control group was treated with Bailing capsules (1 g, po, tid)and the treatment group was treated with azithromy-cin tablets (250 mg, po, qd)combined with Bailing capsules(1 g, po, tid).The course of treatment was 6 months and all the patients were followed up for 6 months after the treatment.The clinical efficacy, lung function, exercise tolerance, quality of life, the times of acute exacerbation and the incidence of adverse drug reactions of the two groups were observed and compared .Results:After the treat-ment, the lung function, exercise tolerance and quality of life were improved significantly in the two groups (P<0.05 or <0.01), and all the indices in the treatment group were significantly better than those in the control group (P<0.05 or <0.01).The total ef-fective rate in the treatment group was higher than that in the control group (P<0.05).The times of acute exacerbation in the treat-ment group were lower than those in the control group (P<0.01).The adverse drug reactions showed no significant difference between the groups (P>0.05).Conclusion:Azithromycin tablets combined with Bailing capsules can improve lung function , enhance exer-cise tolerance , improve the quality of life and reduce the frequency of acute exacerbation effectively with good security in the treatment of patients with COPD in stable phase .