Mammalian target of rapamycin(mTOR)locates at the downstream of phosphatidylinositol 3 kinase(PI3K)-protein kinase B(Akt)cell signal transduction pathway. Studies find that the abnormal activa-tion of this pathway is correlated with the endocrine and drug resistance of anti human epidermal growth factor receptor-2(HER-2)target therapy in breast cancer. The combination with mTOR inhibitors based on the past traditional drugs can block the pathway and reflect a favourable application prospect in preventing the develop-ment of resistance and restoring the initial sensitivity on tumor cells. mTOR inhibitors are expected to be the new hope for the treatment of breast cancer.