Human epidermal growth factor receptor 2 (HER2)-targeted therapy has greatly improved the prognosis of HER2-positive breast cancer. HER2-targeted therapy combined with chemotherapy dominated by trastuzumab+ pertuzumab is important in the neoadjuvant therapy, postoperative adjuvant therapy and late-stage standard treatment for HER2-positive breast cancer. Antibody-drug conjugates (ADCs) and tyrosine kinase inhibitors (TKIs) have further improved the efficacy of therapy. However, advanced breast cancer will eventually get a recurrence or drug resistance. HER2-positive breast cancer is characterized by moderate immunogenicity with the presence of large tumor-infiltrating lymphocytes (TILs), which provides a theoretical basis for immunotherapy. The application of HER2-targeted cancer vaccines and immune checkpoint inhibitors is promising and would offer more treatment options for the patients.