Aim: Acute lung injury (ALI), a critical illness syndrome with high morbidity and mortality, is characterized by a severe inflammatory response. Dioscin exerts protective effects against crystalline silica-induced pulmonary inflammation and fibrosis in mice. Bleomycin (BLM) is widely used to induce ALI and fibrosis in animal models. This study aims to investigate the effects of dioscin on BLM-induced ALI in mice. Methods: C57BL/6 mice were intratracheally injected with BLM to induce ALI. Lungs and bronchoalveolar lavage fluids were then harvested on day 7 for evaluation. Changes in tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and interleukin-10 (IL-10) expression level were measured by RT-qPCR and ELISA. Protein expressions of nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), and high-mobility group box 1 (HMGB1) were measured by western blot. Results: Dioscin protects against BLM-induced ALI by decreasing the numbers of total and inflammatory cells, lung edema, myeloperoxidase activity, and malondialdehyde content. Moreover, dioscin significantly inhibited TNF-α, IL-1β, NF-κB, COX-2, and HMGB1 levels, and upregulated IL-10 levels. Conclusion: Our data indicate that dioscin attenuates oxidative stress, the lung inflammatory response, and acute lung injury in BLM-challenged mice.