Objective Investigate the effects of salvianolic acid A on rats of bleomycin-induced pulmonary fibrosis and potential mechanisms. Methods Single-dose bleomycin was given via intratracheal on Day 0 and rats were treated from Day1 daily with tail-vein injection of salvianolic acid A for 28 d. Record weights and observe general physical sign. Measure free radical、pulmonary function and take electron microscopes. Results Salvianolic acid A could recover physical sign, enhance SOD and MDA activities and reduce MDA contents. Salvianolic acid A could minimize of alveolar spaces and alleviate the inflammation. Moreover, it could improve pulmonary function and decrease collagen expression, inhibits type Ⅱ alveolar epithelial cells hyperplasia in pulmonary fibrosis rats. Conclusion Salvianolic acid A could attenuate the bleomycin induced pulmonary fibrosis of rats and potential mechanism may be correlated with antioxidation of SAA.