Objective　To　explore　the　viral　etiology　of　human　breast　cancer　to　determine　whether　there　are　novel　molecular　targets　for　gene　therapy　of　breast　cancer　and　provide　evidence　for　the　research　of　gene　therapy　and　vaccine　development　for　breast　cancer.　Methods　PCR　was　used　to　screen　HPV16　and　HPV18　oncogenes　E6　and　E7　in　the　SKBR3　cell　line　and　in　76　paraffin　embedded　breast　cancer　tissue　samples.　RNA　interference　was　used　to　knock　down　the　expression　of　HPV18　E6　and　E7　in　SKBR3　cells,　then　the　changes　in　the　expression　of　cell-cycle　related　proteins,　cell　viability,　colony　formation,　metastasis,　and　cell　cycle　progression　were　determined.　Results　HPV18　oncogenes　E6　and　E7　were　amplified　and　sequenced　from　the　SKBR3　cells.　Of　the　patient　samples,　6.58%　and　23.68%　were　tested　to　be　positive　for　HPV18　E6　and　HPV18　E7.　In　the　cell　culture　models,　the　knockdown　of　HPV18　E6　and　E7　inhibited　the　proliferation,　metastasis,　and　cell　cycle　progression　of　SKBR3　cell.　The　knockdown　also　clearly　affected　the　expression　levels　of　cell　cycle　related　proteins.　Conclusion　HPV　was　a　contributor　to　virus　caused　human　breast　cancer,　suggesting　that　the　oncogenes　in　HPV　were　potential　targets　for　gene　therapy　of　breast　cancer.