Aim To study the change of the interleukin-8 (IL-8) content in blood and cerebrum after cerebral ischemia-reperfusion injury. Methods With Zea Longa's thread method, cerebral ischemia-reperfusion injury model of rats was established. The rats were randomly divided into the groups as sham operated control group and ischemia-reperfusion 3 h, 6 h, 12 h, 24 h and 48 h groups. The content of IL-8 in blood serum and brain tissue was detected by double antibody sandwich enzyme-linked immunosorbent assay. Results The content of IL-8 in blood serum was increased significantly at 3 h after reperfusion (p<0.01), and then went down. It reached the level of the control group at 24 h after reperfusion. The concentration of IL-8 in brain tissue was peaked at 6 h after reperfusion (p<0.01), went down after 12 h reperfusion. Moreover, there is no difference between the group of 6 h after reperfusion and 12 h after reperfusion (p>0.05). Conclusion IL-8 was involved in the pathophysiological course of cerebral ischemia-reperfusion injury.