Objective To explore the mechanism of Buyang Huanwu decoction in inhibiting pulmonary neutrophil inflammatory activation under the pathological condition of acute respiratory distress syndrome (ARDS). Methods The bronchoalveolar fluid (BALF) of ARDS patients treated and untreated by Buyang Huanwu decoction were obtained, and the contents of inflammatory factors (tumor necrosis factor α［TNF-α］, interleukin ［IL］-1β, IL-6, and IL-4) were detected by enzyme-linked immunosorbent assay (ELISA). Neutrophils were isolated at the same time, and the expression of IL-4 receptor α (IL-4Rα), hypoxia-inducible factor 1α (HIF-1α) and cleaved cysteine aspartic acid specific protease (caspase) 3 was detected by Western blotting. The primary neutrophils with silenced IL-4Rα were pretreated with rats drug serum of Buyang Huanwu decoction, and then ARDS in vitro model was established by lipopolysaccharide (LPS) and hypoxia induction. The contents of inflammatory factors in cell supernatant were detected by ELISA, the cell proliferation activity and apoptosis were detected by cell counting kit 8 and flow cytometry, respectively. Results Compared with the routine treatment group, the contents of TNF-α, IL-1β and IL-6 in the BALF of Buyang Huanwu decoction treatment group were significantly decreased (all P＜0.01), while the content of IL-4 was increased slightly (P＞0.05). Compared with the patients in the routine treatment group, the expression of IL-4Rα and cleaved caspase 3 was significantly increased in the BALF-derived neutrophils of ARDS patients in the Buyang Huanwu decoction treatment group, while the expression of HIF-1α was significantly decreased (all P＜0.01). Compared with neutrophils cultured under normal conditions, the contents of TNF-α, IL-1β and IL-6 were significantly increased in the supernatants of neutrophils cultured under LPS and hypoxia for 48 h, and the cell proliferation activity was also significantly increased (all P＜0.01). Compared with the cells of the ARDS in vitro model, the contents of the above inflammatory factors were significantly decreased in the supernatants of neutrophils pretreated with Buyang Huanwu decoction drug serum, the cell proliferation activity was significantly decreased, the apoptosis rate was significantly increased (all P＜0.01), while IL-4Rα silencing could reverse the above effects of Buyang Huanwu decoction drug serum (all P＜0.01). Conclusion Buyang Huanwu decoction can inhibit the release of inflammatory factors from neutrophils under ARDS by up-regulating IL-4Rα.