Abstract: 【Abstract】 Objective To explore effect of brain-derived neurotrophic factor (BDNF) on IL-6 expression in the lung of rats with brain ischemia. Methods Inflammatory lung injury was induced by brain ischemia in rats that were devided into sham operation group, brain ischemia lung injury (BILI) group and brain ischemia with BDNF administration group. Lungs were harvested from rats in each group in 3 days after brain ischemia respectively. Immunohistochemistry, RT-PCR and Western blot were employed to detect the expressional changes on the mRNA and protein of IL-6 in the lung tissues. Results Expression of IL-6 was mainly found in cytoplasm of lung epithelial cell and macrophage with immunohistochemistry staining. A significant decrease of IL-6 expression was observed at 3 days after brain ischemia with BDNF antibody block. Conclusion BDNF, as a crucial neurotrophic factor, could regulate IL-6 expression in rats lung tissues with brain ischemia.