Kidney gene expression profile of db/db diabetic nephropathy mice was analyzed by using Affymetrix oligonucleotide genechip. Mice diabetic nephropathy related genes (and ESTs) were found out. A 1.7 kb cDNA was amplified and cloned by using RACE method, based on the sequence of EST. Homologous analysis of the sequence was carried out. And the result shows that it is part of mouse expression sequence AL023001, which function is unknown. To further investigate the relationship between AL023001 and diabetic nephropathy, the function of AL023001, expression levels of AL023001 were analyzed quantitatively using RT-PCR method. Result of RT-PCR shows that AL023001 is expressed differentially in liver, muscle, brain and fat, while the expression pattern of AL023001 in kidney is just like that revealed by gene chip. These results suggest that AL023001 is related to mice diabetic nephropathy, though its function and possible role played in the development of mice diabetic nephropathy still to be investigated.