Mutant or aberrant regulation of expressing products of p53 gene results in losing its tumor suppressive function,which is often seen in many malignancies,including breast cancer.Oncoprotein MDM2 plays a primary role in regulating P53,and these two form an automregulatory feed back loop.mdm 2/p53 pass way performs important function in development,progression,therapy and prognosis of breast cancer.Besides,more and more studies show that some other molecular markers in breast cancer,such as PI3K/Akt/mTOR, p14ARF, and Her2/neu can regulate this passway unneglectedly.The purposeof this reviewis to summarize not only the relations betweenmdm 2/p53 passway and pathological charac-ters,therapy and prognosis of breast cancer,but also the relations of this passway with some other molecular proteins in breast cancer.