Abstract： Objective To observe the protective effect of aprotinin on the cerebral ischemia-reperfusion injury. Methods Rat model of cerebral ischemia-reperfusion injury was created by the middle cerebral artery embolization. The changes of IL-1β,IL-6 and IL-8 content in the brain tissue were measured by ELISA. The neurological scores were made on Zea Longa 5-point scale. Results In model group, the IL-1β,IL-6 and IL-8 protein content began to increase slightly at 3 hours compared with sham group, reached the peal[at 12 hours. In the aprotinin treated group, aprotinin reduced the protein content. It showed no significant difference between model group and aprotinin treated group at 3 hours, however and there was greatly difference at 6,12 and 24 hours between these two groups. Conclusion The present study provides in vivo evidence that aprotinin protects brain against cerebral ischemia-reperfusion injury. The mechanism is related to the decrease of cerebral levels of IL-1β,IL-6 and IL-8.