Objective: To study the efficacy and safety of high-dose ambroxol combined with levofloxacin in elderly chronic obstructive pulmonary disease (COPD) patients with severe pneumonia. Methods: A total of 100 elderly patients with COPD with severe pneumonia from June 2016 to June 2019 were selected and randomly divided into an observation group and a control group, each with 50 cases. Both groups of patients were treated with levofloxacin. Based on this, the control group was given a conventional dose of ambroxol, and the observation group was given a large dose of ambroxol. The treatment effects were compared between the 2 groups. Results: After the treatment, the levels of lung function indicators such as FVC and FEV1 in the observation group were higher than those in the control group (P<0.05); the levels of inflammation indicators such as TNF-α and CRP in the observation group were lower than those in the control group (P<0.05); oxidative stress indicators In terms of levels, the SOD level in the observation group was higher than that in the control group, and the MDA level was lower than in the control group (P<0.05). There were no significant differences in the adverse reactions between the two groups (P>0.05). Conclusion: The use of high-dose ambroxol combined with levofloxacin in elderly patients with chronic obstructive pulmonary disease with severe pneumonia can significantly improve the pulmonary function of patients, effectively relieve the patient's inflammatory level, improve the patient's oxidative stress level, and have high drug safety , the effect is reliable and worthy of promotion.