Objective: To investigate the effect of Jinshuibao capsule on pulmonary function and immune function (Th17/Treg) in stable patients with chronic obstructive pulmonary disease (COPD). Method: Seventy-six patients with COPD were randomly divided into 2 groups;38 patients in the control group took tiotropium bromide powder for inhalation alone

18 μg daily;38 patients in the treatment group added Jinshuibao capsule

3 capsules each time

3 times daily;the patients in two groups received 3-month period of treatment. Clinical efficacy

clinical symptoms

pulmonary function and immune function (Th17/Treg) changes in two groups were observed before and after the treatment. Result: ①The total effective rate of the treatment group and the control group were 88.6% and 77.1% respectively(P<0.05). ②After the treatment

symptom score of the treatment group was significantly decreased (P<0.01)

and the improvement of clinical symptoms in the treatment group was better than that in the control group (P<0.01). ③After the treatment

forced expiratory rolume in one second(FEV1)

FEV1% and FEV1/forced vital capacity(FVC)% in the treatment group were increased (P<0.01)

there was statistical difference as compared with that in the control group (P<0.05

P<0.01). ④After the treatment

Th17% and Th17/Treg in the treatment group were increased (P<0.01)

there was statistical difference as compared with that in the control group (P<0.05). Conclusion: Jinshuibao capsule combined with tiotropium bromide powder for inhalation had clear efficacy in improving patient's clinical symptoms and pulmonary function in stable COPD. The mechanism may be achieved by adjusting peripheral Th17/Treg ratio and improving patient's immune function.