Objective:To study the gene expression of nuclear factor erythroid-2-related factor 2 (Nrf2), glutathione-S-transferase (GST) and interleukin-1 β (IL-1β) in A549 cells exposed to hyperoxia and cell apoptosis after siRNA interference with Nrf2.Method:Normal A549 cell lines were assigned into normoxia+siRNA group, normoxia+control group, hyperoxia+siRNA group and hyperoxia+control group according to whether siRNA interference was used and the exposure environment (normoxia/hyperoxia). The hyperoxia environment contained 95%O 2 and 5%CO 2. The levels of mRNA expression of Nrf2, GST and IL-1β were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Flow cytometry was used to examine cell apoptosis of the hyperoxia+control group and hyperoxia+siRNA group at different time points. Analysis of variance (ANOVA) was used to test the relative gene expression and apoptosis of A549 cells. Result:(1) Compared with the normoxia+control group, the expression of Nrf2 and GST in the hyperoxia+control group was significantly increased ( P<0.05), and the expression of IL-1β was significantly decreased ( P<0.05); the expression of Nrf2 and GST in the normoxia+siRNA group decreased significantly ( P<0.05), while the expression of IL-1β increased significantly ( P<0.05). (2) Compared with the normoxia+siRNA group, Nrf2 expression in the hyperoxia+siRNA group showed no significant changes ( P=0.230), GST expression increased slightly ( P=0.057), and IL-1β expression decreased slightly ( P=0.112). (3) Compared with the hyperoxia+control group, the expression of Nrf2 and GST in the hyperoxia+siRNA group decreased significantly ( P<0.05), and the expression of IL-1β increased significantly ( P=0.042). (4) Compared with the hyperoxia+control group, the apoptosis of A549 cells in the hyperoxia+siRNA group increased significantly at 24 h, 48 h and 72 h ( P<0.05). Conclusion:After interfering with Nrf2, siRNA may regulate the expression of GST and IL-1β, preventing oxidative stress, reducing inflammatory response and inhibiting apoptosis.