Insulin-like growth factor 2 gene was one of important genes controlling muscle growth and fat deposition in animals. In this study,we isolated 5 475 bp IGF2 including complete coding sequence 669 bp which interrupted by 3 introns and encoded 222 amino acids from GIFT strain Nile Tilapia Oreochromis niloticus. Total eleven SNPs were found at GIFT strain Nile Tilapia O. niloticus IGF2 exons and introns through comparing sequences from 10 individuals. The genetypes of intron 1 621 nt and exon 3 161 nt were studied and the correlation of fish shape,weight gain with different genetypes were analyzed in this paper. Tetra-primers ARMS was performed to detect the SNP locus at 621 nt ( C /T) of intron 1. The results indicated that the frequencies of CC,CT and TT were 0. 32,0. 32 and 0. 36 in male population,and 0. 38,0. 38 and 0. 24 in female population respectively; there was only a remarkable correlation between different genotypes with male GIFT strain Nile tilapia O. niloticus body shape (height /length) (P < 0. 05),CC individuals were significantly higher than CT and TT individuals. The SNP locus at 167 nt ( A /G) of exon3 was a nonsense mutation but it changed the restriction site of MSP Ⅰ. So PCR-RFLP was used to detect the genotypes,only GG and AG individuals were found,with the frequencies of GG and AG 0. 71 and 0. 19 in male population and 0. 75 and 0. 25 in female population respectively; there was only a remarkable correlation between different genotypes with male GIFT strain Nile tilapia O. niloticus weight gain ( P < 0. 01),GG individuals were obviously higher than AG ones.