Chronic obstructive pulmonary disease (COPD) is a disease characterized by frequent acute exacerbations (AEs), especially in severe and very severe cases. We aimed to evaluate the efficacy and safety of Bu-fei Yi-shen granules (BYGs) for COPD.We conducted a multicenter, randomized, double-blinded, placebo-controlled trial of 348 COPD patients with GOLD 3-4 COPD. The patients were randomly assigned into experimental or control groups in a 1:1 ratio. Patients in the experimental group were prescribed BYG, while those in the control group were administered a placebo, orally, twice daily, with 5 days on and 2 days off per week for 52 weeks. The outcomes included AEs, pulmonary function, clinical signs and symptoms, dyspnea scores (mMRC), quality of life scores, and a 6-minute walk test (6MWT).A total of 280 patients completed the trial, including 135 patients in the experimental group and 145 in the control group. Compared to the control group, significant differences were observed in frequencies of AEs (mean difference: -0.35; 95% CI: -0.61, -0.10; P = 0.006) and AE-related hospitalizations (-0.18; 95% CI: -0.36, -0.01; P = 0.04), 6MWD (40.93 m; 95% CI: 32.03, 49.83; P < 0.001), mMRC (-0.57; 95% CI: -0.76, -0.37; P < 0.001), total symptoms (-2.18; 95% CI: -2.84, -1.53; P < 0.001), SF-36 (11.60; 95% CI: 8.23, 14.97; P < 0.001), and mCOPD-PRO (-0.45; 95% CI: -0.57, -0.33; P < 0.001) after treatment. However, there were no significant differences in mortality, pulmonary function, and mESQ-PRO scores (P > 0.05). No obvious adverse events were observed.BYG, as compared to a placebo, could significantly reduce the frequencies of AEs and AE-related hospitalizations for GOLD 3-4 COPD patients. Clinical symptoms, treatment satisfaction, quality of life, and exercise capacity improved. There was no significant improvement in mortality and pulmonary function.© 2023 Yu et al.