Abstract: Immune checkpoint plays an important role in maintaining self-tolerance and preventing immune system from attacking normal tissues. Tumor cells take advantage of these mechanisms to evade immune recognition. At present，the most important immune checkpoints are cytotoxic T-lymphocyte antigen-4（CTLA4），programmed death-1（PD-1）and programmed death ligand-1（PD-L1）. PD-L1 binds PD-1 to reduce the cellular immune response by inducing T-cell apoptosis or exhaustion. Immune checkpoint blockade improves the survival of patients with cancer. Despite the limited understanding，checkpoint blockade as a novel therapeutic approach may change the treatment paradigm of breast cancer in the future. In this paper，recent advances of immune checkpoint blockade in breast cancer are reviewed.