Blood samples from fifty xinyang buffalos were extracted for genomic DNA and the primers for PRL gene (NC007324) were designed to detect the polymorphisms in the second，fourth and fifth exons of this gene by PCRSSCP and DNA sequencing， then the correlations between the polymorphisms and the growth traits of the buffalos were analyzed. The PCRSSCP and DNA sequencing showed that in the tested buffalos each exon had shifted SSCP band and there was one SNP in each exon (2974G>A，7581G>A，8558 G>). The correlation analysis showed that the hucklebone widths in the buffalos genotyped AA were significantly (P<0.05) greater than those in the buffalos genotyped BB based on the second exon polymorphisms.