PCR-RFLP technique was applied in this study to analyze the polymorphism of intron 1 of porcine MyoD1 gene in 3 pure breeds (Tongcheng,Landrace,Yorkshire) and 2 crossbred breeds (LYT,YLT).There was a base transition in the 257th nucleotides of intron 1 (C-A),which lead to the change of DdeⅠdigestion site.PCR products digested with DdeⅠindicated that there were two alleles，three genotypes.The C allele was predominant in Tongcheng pigs，while the frequency of A allele and C allele was close in other groups.The relationship with growth,carcass and meat quality traits revealed that different genotypes were related with meat color score and water loss rate (P<0.05 or P<0.01).Meat color score with CC genotype was significant higher than AA and AC genotype (P<0.05),but the water loss rate was extremely significant lower than that with AA genotype (P<0.01).So the meat quality of individual with CC genotype was better.These results confirmed that MyoD1 gene was an important candidate gene for meat quality,and the polymorphism of the 257th nucleotides of intron 1 offered molecular marker for marker assisted selection of porcine meat quality.