[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin（PRL） gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,the polymorphism of intron 1 of PRL gene was detected by PCR-RFLP method.And the relationship between the gene polymorphism and body size traits was analyzed.[Result]Intron 1 in PRL gene of Jingjiang Partridge Duck had sequence polymorphism.Two kinds of genotypes（AB and BB） were detected by DraⅠrestriction and genotype BB was dominant in population（91.67%）.The results of Chi-square test indicated that this site was in Hardy-Weinberg equilibrium in Jingjiang Duck（P 〉0.05）.The results of least square analysis showed that the ducks with AB genotype had larger pelvis breadth（P 〈0.01） but smaller chest measurement（P 〈0.05） than those of BB ducks.[Conclusion]It was preliminarily concluded that PRL gene could be regarded as useful candidate gene（marker） for part of body size traits of Jingjiang Partridge Duck and part of body size traits can be improved by allele selection.
