Following spinal cord ischemia/reperfusion injury, an endogenous damage system is immediately activated and participates in a cascade reac-tion. It is dififcult to interpret dynamic changes in these pathways, but the examination of the transcriptome may provide some information. The transcriptome relfects highly dynamic genomic and genetic information and can be seen as a precursor for the proteome. We used DNA microarrays to measure the expression levels of dynamic evolution-related mRNA after spinal cord ischemia/reperfusion injury in rats. The abdominal aorta was blocked with a vascular clamp for 90 minutes and underwent reperfusion for 24 and 48 hours. The simple ischemia group and sham group served as controls. After rats had regained consciousness, hindlimbs showed varying degrees of functional impairment, and gradually improved with prolonged reperfusion in spinal cord ischemia/reperfusion injury groups. Hematoxylin-eosin staining demon-strated that neuronal injury and tissue edema were most severe in the 24-hour reperfusion group, and mitigated in the 48-hour reperfusion group. There were 8,242 differentially expressed mRNAs obtained by Multi-Class Dif in the simple ischemia group, 24-hour and 48-hour reperfusion groups. Sixteen mRNA dynamic expression patts were obtained by Serial Test Cluster. Of them, ifve patts were signiifcant. In the No. 28 patt, all differential genes were detected in the 24-hour reperfusion group, and their expressions showed a trend in up-regu-lation. No. 11 patt showed a decreasing trend in mRNA whereas No. 40 patt showed an increasing trend in mRNA from ischemia to 48 hours of reperfusion, and peaked at 48 hours. In the No. 25 and No. 27 patts, differential expression appeared only in the 24-hour and 48-hour reperfusion groups. Among the ifve mRNA dynamic expression patts, No. 11 and No. 40 patts could distinguish normal spinal cord from pathological tissue. No. 25 and No. 27 patts could distinguish simple ischemia from ischemia/reperfusion. No. 28 patt could analyze the need for inducing reperfusion injury. The study of speciifc pathways and functions for different dynamic patts can provide a theoretical basis for clinical differential diagnosis and treatment of spinal cord ischemia/reperfusion injury.