Abstract: By applying PCR and sequencing technique, the polymorphism and genetic differentiation of porcine growth hormone gene in 65 individuals form 11 pig breeds were studied.43 SNPs loci and 7 bp lack segment within intron 3 were found. Analysis results showed that the variance is different at different function region The percentage of SNPs loci in exon region, intron region and 5'UTR and 3'UTR region are 1860%, 74.42% and 6.98%. There are 8 SNPs loci in exon region which bring about 4 amino acid loci variation, exon 2 is the high variation region.The variance of SNPs loci belongs to neutral mutation The pGH gene haplotype among 11 breeds is unique. Results of AMOVA analysis showed that the variation of pGH gene sequence is higher in interbreeds (Percentage of variation is 73.45%) than interbreeds （Percentage of variation is 26.55%）, the diversity among breeds is significant at 0.01, and the genetic differentiation of pGH gene is significant The main favorable factor affecting pGH gene evolution and breeds genetic differentiation is intron region. The genetic differentiation among breeds is related to gene flow and geographic distribution