Chronic obstructive pulmonary disease (COPD) is a severe condition that leads to premature mortality and places a significant financial burden on healthcare systems. An adjunctive therapy in COPD includes the simultaneous administration of astragalus injection and ambroxol hydrochloride. Despite its widespread use, the effectiveness of this combined approach in COPD treatment has not been systematically evaluated. Thus, we conducted a systematic review and meta-analysis to assess the efficacy of combining astragalus injection with ambroxol hydrochloride as an adjuvant treatment for COPD. Six electronic databases were used to search for relevant randomized controlled trials, and data analysis was conducted using Review Manager 5.4. A total of 14 randomized controlled trials were included, involving 1070 patients who met the criteria. The results of the meta-analysis indicated that the combination of astragalus injection with ambroxol hydrochloride as an adjuvant treatment can improve various clinical parameters in patients with COPD compared to conventional treatment alone. These parameters include the clinical effective rate (OR = 5.44, 95% CI 3.51–8.43, I2 = 0%), partial pressure of oxygen in artery (MD = 1.12, 95% CI 0.87–1.36, I2 = 5%), partial pressure of carbon dioxide in artery (MD = − 1.43, 95% CI − 1.65 to − 1.21, I2 = 0%), forced expiratory volume in one second (MD = 0.30, 95% CI 0.18–0.42, I2 = 0%), percentage of forced expiratory volume in one second (MD = 16.18, 95% CI 12.60–19.76, I2 = 82%), forced vital capacity (MD = 0.33, 95% CI 0.21–0.45, I2 = 36%), hemoglobin (MD = − 16.17, 95% CI − 20.84 to − 11.51, I2 = 29%), and the ratio of forced expiratory volume in one second to forced vital capacity (MD = 2.51, 95% CI − 0.05 to 5.06, I2 = 0%). The combination of astragalus injection and ambroxol hydrochloride could be a selection of COPD patients as an adjuvant treatment. However, further validation is required to evaluate the effectiveness of combining astragalus injection and ambroxol hydrochloride as an adjunctive treatment for patients with COPD.