To explore the effects on lung function and immune function in patients with stable chronic obstructive pulmonary disease (COPD) by using Jinshui Liujun Decoction combined with Western medicine. Methods:A total of 160 patients with stable COPD admitted to the Department of Geriatrics of our hospital from January 2015 to June 2018 were selected as the research objects, and were randomly divided into an observatin group and a control group, with 80 cases in each group. The control group was treated with conventional Western medicine, while the combined Jinshui Liujun Decoction group was treated with Jinshui Liujun Decoction on the basis of the routine group. The lung function, immune function, immunoglobulin and clinical effectiveness were compared between the 2 groups. Results:After treatment, the clinical effective rate of the observation group was 86.25%, which was significantly higher than the clinical effective rate of the control group (68.75%) (P<0.05). After treatment, the 2 groups of immunoglobulin (IgA, IgG and IgM), lung function (FEV1, FEV1 and FEV1/FVC), immune function (CD4+, Th17 and Th17/Treg) were significantly improved compared to those before treatment (P<0.05). The above indicators in the observation group were higher than those in the control group after treatment (P<0.05). After treatment, the CD8+ of the 2 groups was lower than that before treatment (P<0.05), and the CD8+ of the observation group was lower than that of the control group (P<0.05). Conclusion:Compared with conventional Western medicine, the addition of Jinshui Liujun Decoction in the treatment of stable COPD can significantly improve the respiratory function of patients with better curative effect, which may be related to the effect of the prescription on immune cells and their cytokines.