Abstract: Objective To investigate the differentially expressed genes in keloids in comparison with normal skin using cDNA microarray.Methods The cDNA microarray consisting of 8064 clones of human genes was employed to detect and screen the differentially expressed genes in keloid and normal skin tissues.Semi-quantitative RT-PCR was applied to verify the results of gene microarray.Results Totally 277 differentially expressed genes were identified in keloids in comparison with normal skin tissue,including 163 up-regulated genes and 114 down-regulated ones according to the designed data filter criteria.These differentially expressed genes belonged to 26 different functional gene families involving different biological processes.RT-PCR yielded results were consistent with those of microarray study.Conclusion A variety of genes are involved in the formation of keloids.The 277 differentially expressed genes comprise the differential gene expression profile of keloids and describe the general changes in the gene expressions in keloid at transcriptional level.Further analysis of the identified genes might help reveal the molecular mechanism of abnormal scarring.