The article reviews the advancements and challenges in CAR-based immunotherapy for breast cancer, focusing on different subtypes such as Luminal A, Luminal B, HER2-positive, and triple-negative breast cancer (TNBC). It highlights the effective and potential targets for CAR-T therapy in these subtypes, particularly in TNBC, where treatment options are limited. The review also discusses the role of the tumor microenvironment (TME) in CAR-T therapy, including the impact of cancer-associated fibroblasts (CAFs), myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and regulatory T cells (Tregs). Additionally, it explores the advantages of CAR-NK cells, CAR-macrophages, and CAR-mesenchymal stem cells (MSCs) in treating breast cancer, emphasizing their potential for safer and more effective therapy. The article concludes by discussing the therapeutic applications of CAR exosomes, which show promise in overcoming the limitations of CAR-T therapy, such as off-target effects and toxicity. Overall, the review underscores the potential of CAR-based immunotherapy to improve the treatment outcomes for breast cancer, especially in TNBC, and highlights the need for further research to address current challenges.The article reviews the advancements and challenges in CAR-based immunotherapy for breast cancer, focusing on different subtypes such as Luminal A, Luminal B, HER2-positive, and triple-negative breast cancer (TNBC). It highlights the effective and potential targets for CAR-T therapy in these subtypes, particularly in TNBC, where treatment options are limited. The review also discusses the role of the tumor microenvironment (TME) in CAR-T therapy, including the impact of cancer-associated fibroblasts (CAFs), myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and regulatory T cells (Tregs). Additionally, it explores the advantages of CAR-NK cells, CAR-macrophages, and CAR-mesenchymal stem cells (MSCs) in treating breast cancer, emphasizing their potential for safer and more effective therapy. The article concludes by discussing the therapeutic applications of CAR exosomes, which show promise in overcoming the limitations of CAR-T therapy, such as off-target effects and toxicity. Overall, the review underscores the potential of CAR-based immunotherapy to improve the treatment outcomes for breast cancer, especially in TNBC, and highlights the need for further research to address current challenges.