Objective:To observe the clinical efficacy of Modified Bushen Naqi Formula combined with Western medicine in the treatment of stable chronic obstructive pulmonary disease (COPD) of the lung-kidney qi deficiency type. Methods108 COPD patients of the lung-kidney qi deficiency type were randomly assigned into treatment group and control group, 54 patients in each group. The control group was given conventional Western medicine therapy, while the treatment group was treated with Modified Bushen Naqi Formula and conventional Western medicine therapy. The treatment course was 6 months in both groups. Changes in TCM syndrome score, modified Medical Research Council (mMRC) dyspnea score, related measures of respiratory muscle strength and related measures of pulmonary ventilation function were observed and compared.  Results:①96 patients completed the trial finally, including 49 patients in the treatment group and 47 in the control group. ②After treatment, the TCM syndrome score decreased significantly in the treatment group (P＜0.05), but there was no significant change in the control group (P＞0.05). The TCM syndrome score was significantly lower in the treatment group than in the control group after treatment (P＜0.05). ③After treatment, P0.1 decreased significantly (P＜0.05) and MEP increased significantly in both groups (P＜0.05); MIP increased significantly in the treatment group (P＜0.05), but there was no significant change in the control group (P＞0.05). P0.1 was significantly lower in the treatment group than in the control group (P＜0.05), while MIP and MEP were significantly higher in the treatment group than in the control group (P＜0.05) after treatment. ④After treatment, IC increased and RV decreased significantly in the treatment group (P＜0.05), but there was no significant change in the control group (P＞0.05). IC increased and RV decreased significantly in the treatment group compared to those in the control group after treatment (P＜0.05); there was no significant difference in the level of FEV,1,% (P＞0.05). ⑤After treatment, the mMRC score was significantly reduced in the treatment group (P＜0.05), but there was no significant change in the control group (P＞0.05). The mMRC score was significantly lower in the treatment group than in the control group after treatment (P＜0.05).  Conclusion:By enhancing respiratory muscle strength to increase deep inspiration and reduce residual volume, Modified Bushen Naqi Formula improves the function of “receiving qi” in COPD patients, relieves the chronic respiratory symptoms of failure of the kidney to receive qi, such as more exhalation than inhalation, shortness of breath and panting, and improves their quality of life.