Uncoupling proteins (UCPs) are mitochondrial membrane transporters, acting as an uncoupler in oxidative phosphorylation. UCPs were also discovered associated with body mass index, resting metabolic rate and percentage of fat. Three haplotypes were detected by PCR-SSCP and then confirmed by DNA sequencing. For the first time, three single strand conformation polymorphisms(SNPs), G-42A, C-50T, and T-51C, were discovered in the promoter region of the UCP2 gene in pigs. T-C-G is close linkage and C-T-A is also linkage. The potential protein factor binding sites were predicted by transcription factor analysis tool TFSEARCH ver1.3 on line. The result clewed that three mutations, T→C(－51), C→T(－50), and G→A(－42) in the promoter region of the UCP2 may have some effect on the regulation of UCP2 gene transcription and regulation because those mutations increase a AML-1a site. There are three different haplotypes which are A , B and AB haplotype detected in Neijiang pig while other pig breeds have only haplotype A, suggesting Neijiang pig have specific property.