BackgroundPulmonary fibrosis (PF) is a common clinically critical disease characterized by high morbidity and high mortality. Forsythiaside A (FA) is a phenylethanol glycoside component in Forsythia suspensa, which has anti‐inflammatory, antioxidant, and antiviral activities. However, the effects of FA on bleomycin (BLM)‐induced PF are unclear.PurposeThe present study explored the role of FA in the amelioration of oxidative stress and apoptosis in BLM‐induced PF as well as the possible underlying mechanisms, in vivo and in vitro.MethodsNetwork pharmacology was used to collect the effects of FA on BLM‐induced PF. Subsequently, further observation of the effects of FA on mice with PF by pulmonary pathological changes, transmission electron microscopy, real‐time polymerase chain reaction, Western blot analysis, immunofluorescence, and immunohistochemistry. An in vitro model was constructed by inducing A549 with transforming growth factor beta‐1 (TGF‐β1) to observe the effect of FA on epithelial cell apoptosis.ResultsNetwork pharmacology predicted signaling pathways such as IL‐17 signaling pathway and Relaxin signaling pathway. The results of in vivo studies showed that FA ameliorated BLM‐induced PF through inhibition of fibrosis, modulation of apoptosis, and oxidative stress. In addition, FA promoted TGF‐β1‐induced apoptosis in A549 cells.ConclusionsThe results of our study suggested that FA could protect mice against BLM‐induced PF by regulating oxidative stress and apoptosis as well as the Epithelial mesenchymal transition pathway.