The complete cDNA sequence of DNaseⅠ was isolated from Litopenaeus vannamei hepatopancreas by RT-PCR and RACE.The full length cDNA of DNaseⅠ was 1 614 bp,consisting of a 5’-noncoding region of 116 bp,a 3’-noncoding region of 289 bp,and an open reading frame of 1 209 bp encoding a polypeptide of 403 amino acids.Real time quantitative PCR analysis revealed that the expression level of DNaseⅠ gene of L.vannamei in hepatopancreas was 16-162 folds higher than that in other 5 selected organs and DNaseⅠ gene of L.vannamei belonged to hepatopancreas type.Furthermore,a DNaseⅠ protein expression system based on Escherichia coli was constructed and functional recombinant DNaseⅠ protein was obtained successfully.