Abstract: Insulin-like growth factor 2（IGF2） plays a key role in the growth, development, reproduction, metabolism and osmotic regulation in vertebrates. In this study, the Diodon hystrix igf2 cDNA sequence of 738 bp was identified by molecular cloning technology, and contains the full-length ORF of 645 bp, encoding 214 amino acids.Multiple sequence alignment analysis revealed that the IGF2 in D. hystrix had high homology with other fishes,suggesting that IGF2 was conservative in teleost. The results of tissue distribution showed that the igf2 gene was mainly expressed in liver and brain, and was not expressed in kidney and testis. The results showed that the igf2 gene had significant tissue expression specificity. This study provided a basis for in-depth study of the regulatory mechanism of igf2 gene in growth and development.