〔Abstract〕 Objective To study the effect of bronchial alveolar lavage (BAL) combined with carbapenems drugs in the treatment of severe pulmonary infection. Methods 88 patients with severe pulmonary infection in The First Affiliated Hospital of Zhengzhou University from April 2018 to April 2019 were divided into control group and observation group according to treatment methods, with 44 cases in each group. The control group was treated with meropenem, and the observation group used BAL treatment based on the control group. Efficacy, lung function [force exhalation volume in one second (FEV1), force lung capacity (FVC)], airway resistance (Raw), serum inflammation factor [C reactive protein (CRP), Calcitogenic (PCT)] level and readmission rate were compared between the two groups before and 2 weeks after treatment. Results The total effective rate of in the observation group was 95.45%, which was higher than 81.82% in the control group, and the difference was statistically significant (P < 0.05); FEV1, FVC of the observation group were higher than those of the control group, and Raw was lower than that of the control group after two weeks of treatment. The differences were statistically significant (P < 0.05); CRP, PCT of the observation group were lower than those of the contral group after 2 weeks of treatment, and the difference were statistically significant (P < 0.05); The re-hospital rate of observation group is 4.65%, lower than that of the control group (19.05%), and the difference was statistically significant (P < 0.05). Conclusion BAL combined with carbapenems drugs has significant efficacy in the treatment of severe pulmonary infection, which can improve lung function, reduce inflammatory response, reduce airway resistance and readmission rate.