Taking BF gene as one of the candidate genes influencing on reproductive traits in present study, this study used PCR-RFLP analyzised the polymorphism of intron 1 of BF gene in Large White sows. A single nucleotide polymorphism (SNP) named as BF-intron 1-C79T was detected. And the three genotypes of CC, CT, TT got fitted Hardy-Weinberg equilibrium with chi2-fitness test. An association analysis was tested between the genetic polymorphism at intron 1 and total number born (TNB), number born alive (NBA), born weight (BW) and placental efficiency (PE) respectively. It showed that, at first parity, the TNB, NBA, BW and PE with CC genotype were higher than those with CT genotype but not significant (P>0.05). Meanwhile, in multiparous sow population, the TNB, NBA and PE with CC genotype were significantly more than those with TT genotype (P<0.05), with increase of 3.45, 3.92, and 23.80%, respectively. Thus BF-intron 1-C79T is suggested to be a potential genetic marker for the breeding on the reproductive traits and placental efficiency.