Objective To study the relationship between metalloproteinases (MMPs) and breast cancer. Methods The literature in recent years on the relationship between the expression of MMPs and breast cancer was reviewed. Results The balance between MMPs and tissue inhibitors of metalloproteinases (TIMPs) is keeping normally kept in human body. Many of the studies showed that the expression of MMPs is increased in breast cancer. Conclusion The growth, invasion and metastasis of breast cancer is closely related with the increased expression of MMPs. This suggests that MMPs is a valuable prognostic marker and TIMPs would be a novel drug against cancer.