Provided is an SgRNA combination, comprising an SgRNA specifically targeting the GGTA1 gene, an SgRNA specifically targeting the CMAH gene and an SgRNA specifically targeting the β4GalNT2 gene. Also provided is a CRISPR/Cas9 vector combination, comprising a GGTA1-CRISPR/Cas9 vector, a CMAH-CRISPR/Cas9 vector and a β4GalNT2-CRISPR/Cas9 vector. Also provided is an applicaton of the CRISPR/Cas9 vector combination in knocking out the GGTA1 gene, the CMAH gene and the β4GalNT2 gene. The knockout rates of the three genes with the specifically targeted SgRNA sequences are respectively 56%, 63%, and 41%. A three genes knockoutpig can be obtained, wherein the three genes related to immune rejectionare knocked out, and heart valves of said pig can be acquired.