PCR-SSCP technique was designed in this study to investigate the effect of MyoG on quality meat chicken (developed by Sichuan Dahen Poultry Breeding Company using local breeds). Four mutations at base position in promoter were detected among individuals in each line, i.e. T/C in locusA and T/A, T/C and A/G in locus B . The least square analysis showed that there were a significant difference between genotypes and breast muscle percentage and some carcass traits (P
<0.05）for locus A. There were a significant difference (P <0.05) in breast muscle weight between AC、AA and AB geno-
types; a significant difference (P <0.05) in leg muscle percentage between CC and AC for locus B, and a extremity signifi-cant difference (P <0.01) in the frequency of genotype muscle Fibre Density for Bothlocus A to locus B. There was no sig-nificant difference (P >0.05) in the other triats. It was concluded from the results that MyoG gene is the major gene affect-ing the muscle fiber traits of chicken or it links with the candidate gene, and the mutation could be used as the molecular genetic marker to select the chickens for Meat Quality traits.