Matrix metalloproteinases(MMPs) are a family of zinc-dependent proteinases involved in the degradation of the extracellular matrix. A great deal of studies showed that they have the important role in invasiveness and metastasis of breast carcinoma. It was recently reported that they also contribute to the genesis and development of primary breast carcinoma. MMPs take part in these processes on various mechanisms. Clinically, MMPs showed values for treatment and judging prognosis of breast carcinoma. At present, the scholars are investigating the mechanisms of MMPs on breast carcinoma by various methods, so as to approach a new pathway for treating breast carcinoma.