Platelets (PLTs), the second most abundant cell type in peripheral blood, are circulating fragments of nucleated cells that originate from the megakaryocytes in the bone marrow and play an important role in hemostasis and initiating wound healing. In recent years, studies have shown that several parameters of PLTs in breast cancer patients are significantly different from those in normal subjects and that PLTs can secrete a variety of cytokines to promote epithelial-mesenchymal transition and proliferation of breast cancer cells. PLTs assist circulating tumor cells to survival in the circulatory system, evade immune attack and promote the growth of metastatic cancer foci. Here, the authors address the role of PLTs in breast cancer in terms of the parameter characteristics of the PLTs in breast cancer patients, the mechanism of interaction between PLTs and breast cancer, and the potential of PLTs in the treatment of breast cancer, so as to provide reference for the diagnosis and treatment of breast cancer.