Abstract: 【Abstract】 Objective To investigate the expression of tumor necrosis factor-α (TNF-α) in the lung tissue of rats with lung injury induced by brain ischemia. Methods The rat model of lung injury induced by brain ischemia was established. At 24 h, 48 h, 72 h after brain ischemia, lung tissues were harvested from each rats, the expressions of TNF-α mRNA and protein and its distributions in the lung tissue were measured by the methods of RT-PCR （n=8）, Western blot （n=8）, and immunohistochemistry （n=5）, respectively. Results The increase of TNF-α mRNA and protein levels were found in the lung tissues after brain ischemia, when compared with sham group （P<0.05）. The morphological study with immunohistochemical staining observed TNF-α positive reaction in epithelial cells and some macrophages in the lung tissues after brain ischemia. Conclusion The expression of TNF-α in the lung tissue could be upregulated in the rats with brain ischemia.