Full-length cDNA sequence of fatty acidbinding protein was isolated from hepatopancreas of Litopenaeus vannamei.The full-length cDNA sequence of fatty acidbinding protein is 1 042 bp,which contains a 113 bp 5′UTR(untranslated region),518 bp 3′UTR(untranslated region),and 411 bp open reading frame(ORF)that encodes 136 amino acid residues.There are typical fatty acidbinding protein domains between 4-26 and 63-79 amino acids residues of Litopenaeus vannamei FABP(LvFABP),and these sequences highly conserve in L.vannamei,Metapenaeus ensis,Italian bee,zebra fish,Atlantic salmon,chicken,swine,human.The phylogenetic analysis based on amino acid sequence shows that LvFABP has the highest similarity(98%)with black tiger shrimp FABP,and has 88%,57%,50%,49%,51%,50%,50% identity with cellular retinoic acidbinding proteins(CRABP)of Metapenaeus ensis,FABP of Italian bee,zebra fish,Atlantic salmon,chicken,swine,human,respectively.The expression of the gene in different tissues was analyzed by semi-quantitative reverse transcription PCR(RT-PCR),the result shows that the expression of the gene was higher in intestinal,gastric,hepatopancreas,muscle tissues,and the expression was decreased in myocardium,and undetectable in eyestalk of normal shrimp tissue.Comparing the expression of the gene in myocardium,hepatopancreas,intestinal,gastric,eyestalk,muscle of IHHNVresistant shrimp to IHHNVinfected shrimp,there was no obvious difference in myocardium,intestinal,gastric and muscle tissues between two kinds of shrimps,but the expression of FABP in hepatopancreas of IHHNVresistant shrimp is higher than IHHNVinfected shrimp,which showed FABP involves in the immune process inhibiting shrimp from being infected by IHHNV.