Objective To investigate the effect of budesonide aerosol on pulmonary ventilation function and inflammatory levels in elderly patients with stable chronic obstructive pulmonary disease (COPD). Methods A total of 98 elderly COPD patients admitted to Department of Respiratory and Critical Care Medicine, Linzhou People’s Hospital from July 2022 to June 2024 were included, and were divided into the control group and the study group by the randomized odd-even method, with 49 cases in each group. On the basis of conventional treatment during the stable period of COPD, the study group inhaled budesonide aerosol and the control group inhaled budesonide formoterol powder inhaler, and after 12 weeks of treatment, the clinical efficacy, pulmonary ventilation function, blood gas indexes, serum inflammatory factors, and incidence rate of adverse reactions of the two groups were compared. Results The total effective rate of the study group was higher than that of the control group (P<0.05). After 12 weeks, the partial pressure of oxygen in artery (PaO2), forced expiratory volume in one second percent predicted (FEV1%pred) and arterial oxygen saturation (SaO2) in the study group were higher than those in the control group (all P<0.05), while the residual gas volume/total lung volume (RV/TLC), partial pressure of carbon dioxide (PaCO2), residual volume (RV), interleukin-17 (IL-17), interleukin-8 (IL-8), high sensitivity C-reactive protein (hs-CRP) and the total incidence rate of adverse reactions were lower in the study group than those in the control group (all P <0.05). Conclusion Budesonide aerosol can effectively improve the pulmonary ventilation function and blood gas indexes in the elderly patients with stable COPD, relieve the inflammatory response, and is safe and effective.