The invention discloses an interlocking SNP site combination related to the sex-linkage Luhua phenotype of Chinese native chickens. The SNP sites comprise SNP1, SNP2 and SNP3, wherein the SNP1 is a position of 267 bp of a CDKN2A gene promoter region and transcription initiation site upstream, the SNP2 is a position of 380 bp of CDKN2A gene intron 1, and the SNP3 is a position of 170 bp of CDKN2A gene exon 1. The invention finds the three SNP sites related to the sex-linkage Luhua chicken phenotype of Chinese native chickens for the first time, and establishes a method for detecting the phenotype and the genotype of sex-linkage Luhua chickens by the SNP sites. The method has the advantages of simple operation, high accuracy, good repeatability and time saving, is available to mutual detection, realizes 100% accuracy, can be used for cultivating auto-sexing commercial strains, performs auto-sexing by using feather colors, is high in accuracy and simple and convenient to operate, saves time and cost, has good application value, and is worthy of great popularization.