ObjectiveTo investigate the protective effect of Dabupi Tang （DBPT） against radiation-induced lung injury （RILI） and to elucidate whether its mechanism involves modulating the inflammatory response mediated by the Janus kinase 1 （JAK1）/signal transducer and activator of transcription 6 （STAT6） signaling pathway. MethodsForty-eight SPF-grade male SD rats were randomized into 6 groups （n=8）： blank control， model， high-dose （24.28 g·kg^-1） DBPT， medium-dose （12.14 g·kg^-1） DBPT， low-dose （6.07 g·kg^-1） DBPT， and high-dose DBPT + AG490 （a JAK1/STAT6 inhibitor， 5 mg·kg^-1）. After two consecutive weeks of gavage， other groups except the blank control group received single-dose irradiation with 8 Gy X-ray to the right lung for the modeling of RILI. Samples were collected 24 h post-irradiation. Hematoxylin-eosin （HE） staining was used to observe lung histopathology. Serum levels of tumor necrosis factor-α （TNF-α）， interleukin-8 （IL-8）， interleukin-6 （IL-6）， and transforming growth factor-β （TGF-β） were measured by enzyme-linked immunosorbent assay （ELISA）. The expression of JAK1， STAT6， phosphorylated JAK1 （p-JAK1）， and phosphorylated STAT6 （p-STAT6） in the right lung tissue were determined by immunohistochemistry and Western blot. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was employed to analyze the transcription levels of JAK1， STAT6 mRNA. ResultsCompared with the blank control group， the model group showed typical pathological features （alveolar structure destruction， interstitial hyperemia， and lymphocyte infiltration） of RILI. Compared with the model group， the DBPT groups （especially the high- and medium-dose groups） exhibited significantly alleviated lung tissue damage. Compared with the blank control group， the model group exhibited elevated serum levels of TNF-α， IL-8， IL-6， and TGF-β （P<0.01）， which were reduced by DBPT in a dose-dependent manner （P<0.05， P<0.01）. Compared with the blank control group， the model group showed decreased p-JAK1/JAK1 and p-STAT6/STAT6 ratios in the lung tissue （P<0.01）. Compared with the model group， DBPT intervention （especially the high dose） increased the p-JAK1/JAK1 and p-STAT6/STAT6 ratios （P<0.05， P<0.01）. Compared with the high-dose DBPT group， high-dose DBPT + AG490 reversed the protective effect of DBPT， leading to aggravated lung injury and increased pro-inflammatory cytokine levels （P<0.05）， confirming the critical role of this pathway. ConclusionDBPT exerts a significant protective effect against RILI. It may activate the JAK1/STAT6 signaling pathway to reduce the release of pro-inflammatory cytokines， thus alleviating RILI. This study suggests that the JAK1/STAT6 pathway is a potential therapeutic target for DBPT in the prevention and treatment of RILI.