Abstract： Objective To investigate the gene-expression profile in kidney of rats during late sepsis (24hours) by using microarray technology in order to offer some clue to revealing the pathogenetic mechanism of sepsis at gene level. Method A total of 30 Wistar rats were selected and divided into model group and control group randomly(random number). The rats of control group were sham operated and the rats of model group received cecal ligature and puncture (CLP) operation. The biomarkers of renal function were assayed and the histopathological changes of kidney in rats were observed under transmission electron microscope 24 hours after operation. Gene chips containing 22 107 rat-genes cDNA were used to exmine gene-expression in kidney of septic rats to sieve the genes with different expressions with software. Data were analyzed by using SPSS version 11.0 software package.Statistical analyses of two independent samples carried out by using t -test. Results Compared with the control group, the levels of blood urea nitrogen (BUN) and creatinine (Cr) of sepsis group were higher (P ＜ 0.01 ). The histopathological changes in kidney of rats demonstrated the establishment of sepsis model successful 24 hours later.Compared with the control group, there were 325 genes with differential expression in model group. Among the known-functional genes, there were 100 up-regulated and 64 down-regulated. Sorted by biological function, the genes were mainly related to metabolism, immunoresponse, cellular signal transduction, apoptosis, ion channel,growth factor and so on. Conclusions A sequence of genes expressed differentially in kidney of rats with late sepsis. Microarray technology played an important role in the research into sepsis mechanisms.