Objective: This study aimed to evaluate the protective effects of Maekmundong-tang (MMDT) on an elastase-induced COPD model. Materials and Methods: The extract of MMDT was treated to A549 cells and elastase-induced COPD mice model. Then, various parameters such as cell-based cytoprotective activity and histopathological findings were analyzed. Results: MMDT showed a protective effect on elastase-induced cytotoxicity in A549 cells. This effect was correlated with analysis for caspase 3 levels, collagen and elastin contents, protein level of Cdk1, and gene expression of TNF-${alpha}$ and IL-$1{eta}$ in A549 cells. MMDT treatment also revealed a protective effect on the elastase-induced COPD mice model. This effect was evidenced via histopathological finding including immunofluorescence stains against elastin, collagen, and caspase 3, and protein level of Cdc2 in lung tissue. Conclusion: These data suggest that MMDT has pharmaceutical properties on COPD. This study can provide scientific evidence for the efficacy of MMDT for clinical application to patients with COPD.