The invention relates to a yak molecular marker-assisted breeding technology in the technical field of animal biology and specifically relates to a yak meat tenderness candidate gene detection kit. The yak meat tenderness candidate gene PCR (polymerase chain reaction)-SSCP (single-strand conformation polymorphism) detection kit is characterized by comprising a PCR solution, DNA (deoxyribonucleic acid) standard samples of CAPN3*B and CAPN3*C, an SSCP detection reagent, deionized water, 10% of ammonium persulfate, a loading denaturation buffer solution, TEMED (N, N, N', N'-tetramethylethylenediamine) and 12% of non-denatured polyacrylamide gel, wherein Arc: Bis in the non-denatured polyacrylamide gel is 37.5: 1; the loading denaturation buffer solution comprises 98% of deionized formamide, 0.025% of bromophenol blue, 0.025% of xylene cyanol FF and 10mmol/L of EDTA (ethylenediamine tetraacetic acid) with pH value of 8.0. The yak meat tenderness candidate gene detection kit provided by the invention has the characteristics of high speed in molecular marker breeding of yak, high sensitivity, low cost and the like.