Heat shock proteins (Hsps) are stress-induced proteins involved in protein folding and maturation. They are divided into six families based on molecular weight: small Hsps, Hsp40, Hsp60, Hsp70, Hsp90, and large Hsps. In breast cancer, Hsps regulate cell functions such as proliferation, metastasis, and apoptosis. They also influence the balance between protective and destructive immune responses in the tumor microenvironment. This review summarizes the roles of major Hsps in breast cancer biology and highlights their potential in diagnosis and therapy. Hsps like Hsp27, Hsp40, Hsp60, Hsp70, Hsp90, and Hsp110 are involved in various aspects of breast cancer progression, including cell survival, metastasis, immune evasion, and drug resistance. Hsp27 is associated with breast cancer development and progression, and its phosphorylation affects cell survival and proliferation. Hsp40 family members have dual roles in breast cancer, acting as both tumor suppressors and promoters. Hsp60 is involved in apoptosis, metastasis, and immune modulation. Hsp70 is overexpressed in breast cancer and contributes to tumor progression and drug resistance. Hsp90 regulates the stability of client proteins and is a promising therapeutic target. Hsp110 is involved in protein folding and has potential as an immunotherapy adjuvant. The review discusses the potential of Hsp inhibitors in breast cancer treatment, noting that while some show promise, challenges remain in their clinical application. Understanding Hsp functions is crucial for improving breast cancer diagnosis and developing more effective therapies.Heat shock proteins (Hsps) are stress-induced proteins involved in protein folding and maturation. They are divided into six families based on molecular weight: small Hsps, Hsp40, Hsp60, Hsp70, Hsp90, and large Hsps. In breast cancer, Hsps regulate cell functions such as proliferation, metastasis, and apoptosis. They also influence the balance between protective and destructive immune responses in the tumor microenvironment. This review summarizes the roles of major Hsps in breast cancer biology and highlights their potential in diagnosis and therapy. Hsps like Hsp27, Hsp40, Hsp60, Hsp70, Hsp90, and Hsp110 are involved in various aspects of breast cancer progression, including cell survival, metastasis, immune evasion, and drug resistance. Hsp27 is associated with breast cancer development and progression, and its phosphorylation affects cell survival and proliferation. Hsp40 family members have dual roles in breast cancer, acting as both tumor suppressors and promoters. Hsp60 is involved in apoptosis, metastasis, and immune modulation. Hsp70 is overexpressed in breast cancer and contributes to tumor progression and drug resistance. Hsp90 regulates the stability of client proteins and is a promising therapeutic target. Hsp110 is involved in protein folding and has potential as an immunotherapy adjuvant. The review discusses the potential of Hsp inhibitors in breast cancer treatment, noting that while some show promise, challenges remain in their clinical application. Understanding Hsp functions is crucial for improving breast cancer diagnosis and developing more effective therapies.