Objective To observe the efficacy of Tongbian Tang（ 通便汤） combined with Lactulose Oral Solution（ Duphalac） in the treatment of chronic obstructive pulmonary disease（ COPD） with constipation. Methods One hundred and twenty patients with COPD constipation were randomized into combining group

Tongbian Tang group and Duphalac group

with 40 cases in each. They were respectively given Duphalac plus Tongbian Tang

Tongbian Tang alone and Duphalac alone（ orally）. The treatment lasted for 2 courses

and 4 weeks as one course. The constipation symptom score of each group were compared before treatment

in the 4th and 8th week of treatment

and one month after treatment. The COPD symptom and sign scores were compared before treatment

in the 8th week of treatment

and one month after treatment. The efficacy and adverse reaction of each group was observed after treatment

and the recurrence rate was compared one month after treatment. Results The overall response rate（ ORR）in combining group was 97. 5%

better than 85. 0% in Tongbian Tang group and 72. 5% of Duphalac group

and the ORR in Tongbian Tang group was significantly better than that in Duphalac group（ P < 0. 05）. The constipation symptom scores in each group in the 4th and 8th week of treatment were all significantly lower than that before treatment（ P < 0. 05）. The cough score

expectoration score and gasp score in Tongbian Tang group were all significantly lower than those in another two groups in the 8th week of treatment and after treatment（ P < 0. 05）. The recurrence rate in Tongbian Tang group was 10. 3%

significantly lower than 29. 7% in combining group and 54. 8% in Duphalac group（ P < 0. 05）. Conclusion In the treatment of COPD constipation

Tongbian Tang combined with Lactulose Oral Solution seems better than Tongbian Tang alone and Duphalac alone

but the recurrence rate of constipation in patients treated with Tongbian Tang alone could be lower than that in those treated with combining treatment.