Breast cancer represents the most prevalent cancer among women globally, constituting approximately 30% of newly diagnosed female malignancies and serving as the second leading cause of cancer-related mortality, accounting for 11.6% of deaths. Despite notable advancements in survival rates and quality of life for breast cancer patients over recent decades-achieved through interventions such as surgery, chemotherapy, radiotherapy, and endocrine therapy-there remains an urgent need for novel therapeutic strategies. This necessity arises from challenges associated with recurrence, metastasis, and drug resistance. The COVID-19 pandemic has accelerated the development of Messenger RNA (mRNA) vaccines at an unprecedented pace, and as a novel form of precision immunotherapy, mRNA vaccines are increasingly being recognized for their potential in cancer treatment. mRNA vaccines efficiently produce antigens within the cytoplasm, specifically activating the immune system to target tumor cells while minimizing the risk of T-cell tolerance. Therefore, mRNA vaccines have emerged as a promising approach in cancer immunotherapy. This review systematically examines the principles, mechanisms, advantages, key targets, and recent progress in mRNA vaccine therapy for breast cancer. Furthermore, it discusses current challenges and suggests potential directions for future research.