Abstract: By PCR approach, exon4, exon5 and exon6 of POU1F1 gene of Landrace, Duroc, Yorkshire, Jiangquhai、Meishan, and w Xiangzhu are amplified, and PCR products contained exon 4,exon6 and the cloning product of exon5 were sequenced. The results showed that exon4 of POU1F1 gene had the Nla Ⅲ polymorphisms characteristics, the mutation was T→C.The sequences were digested by Nla Ⅲ, and two different genotypes(GG and HH) were produced; but exon 5 and exon 6 of POU1F1 gene were high conservation in the six pig breeds. The result of homologous analysis showed that the homologous rate of nucleotide sequences of the exon4 in human, pig, mouse and cow was 93.9%、86.7%、92.1% respectively and the amino acid sequence of POU specific domain encoded by exon4 of POU1F1 gene in human, pig ,mouse and cow was identical. And the result of homologous analysis of nucleotide sequences encoding POU1F1 POU-homeo domain in human, pig, mouse, cow was 91.4%、85.1%、87.9% respectively, the homologous rate of the amino acid sequence of POU-homeo domain was 96.6%、94.8%、90.2% respectively. This showed that the sequences of the POU1F1 POU-homeo domain and the POU-specific domain encoded by exon4 in mammals were high conservation, pigs could be used to establish animal models of related diseases, providing scientific foundation and serving for human medicine.