Abstract： Objective To analyze the gene expression profiling in the periinfarct cortex in the late stage after stroke onset in renovascular hypertensive rats (RHRs) with gene chip technology.Methods RHRs were induced by the method of Goldblatt's 2k2c operation. Cerebral infarction was also induced by permanent middle cerebral artery occlusion (pMCAO) in RHRs. Sham-operated group was established as controls. Total RNA was extracted from the perinfarct cerebral cortex in injured hemisphere 7 d after pMCAO, and the RNA was performed fluorescence labeling, followed by hybridization with 5705 oligo chips. And then, scanning was performed; the data was collected and chosen for microarray analysis using oligonucleotide arrays. Resuits In total, 197 genes were expressed differentially, including 174 genes up-regulated expression and 23 genes down-regulated expression. The up-regulated genes were distributed among all 12 functional categories; the down-regulated genes were distributed only in the categories of transport, transcription regulator, signal,response to stress, metabolism and cell adhesion. Among the 12 functional categories, only 17differentially expressed genes were not previously reported to be associated with brain ischemia/infarction. Conelusion Active gene expression at late stage of cerebral infarction may imply the molecular mechanisms of injury or repair, being the targets of therapeutic intervention.