To identify molecular markers associated with growth traits in mandarin fish （Siniperca chuatsi） and to facilitate the selective breeding of superior varieties， single nucleotide polymorphism （SNP） loci were screened based on the genomic DNA sequences of the growth-related genes mstn and mtor.A subsequent correlation analysis between these loci and growth traits revealed the identification of three SNPs： mstn-in2， mtor-in26， and mtor-E11.The polymorphism information content （PIC） for these three SNPs ranged from 0.280 8 to 0.372 9， indicating moderate levels of polymorphism in both the Guizhou and Guangdong populations.Marker-trait association analysis revealed the following findings： In the Guizhou population， individuals with the GG genotype at the mstn-in2 locus exhibited significantly higher mean values for total length， body length， and body mass compared to those with the CC genotype （P<0.05）.Similarly， in the Guangdong population， individuals with the GG genotype at the mstn-in2 locus showed significantly higher mean values for total length， body length， body height， and body mass than those with the CC genotype （P<0.05）.Furthermore， in the Guangdong population， individuals with the TT genotype at the mtor-in26 locus exhitied significantly higher mean values for total length， body mass， and Fulton’s condition factor compared to those with the TC or CC genotypes （P<0.05）.These findings indicate that the GG genotype at the mstn-in2 locus and the TT genotype at the mtor-in26 locus are advantageous for growth.Therefore， the mstn and mtor genes are proposed as important candidate genes for molecular marker-assisted breeding programs in mandarin fish.