Abstract: The cDNA of lysozyme was cloned from Parapenaeopsis Hardwickii by RT-PCR and RACE techniques.The complete cDNA sequence of lysozyme is 711 bp,consisting of a 5-\mathrmUTR of 40 bp and 3UTR of 209 bp with a polyadenylation signal sequence AATAAA and a poly (A) tail,the length of ORF is 462 bp encoded a polypeptides of 153 amino acid with a signal peptide of 18 amino acid and a mature protein 135 amino acids.This lysozyme presumed to be a chicken-type lysozyme for it possesses two catalytic sites,eight cysteine residues and one \mathrmCa^2+ binding site.This work provides a basis for further studying of activity of the lysozyme.