Background: A large class of proteolytic enzymes known as cysteine cathepsins are created as pro-enzymes and are activated in slightly acidic conditions. They are crucial for both healthy cellular function and illness. Cysteine cathepsins are a family of proteases that play important roles in a variety of cellular processes, including protein turnover, cell adhesion, and migration. Main body: In breast cancer, cysteine cathepsins have been shown to be overexpressed in tumor cells and to be associated with poor prognosis. This review article discusses the role of cysteine cathepsins in breast cancer, focusing on their diagnostic potential. The article provides an overview of cysteine cathepsins, including their structure, function, and regulation in addition to the evidence for the overexpression of cysteine cathepsins in breast cancer and their association with a poor prognosis. Conclusions: The current review demonstrates the potential use of cysteine cathepsins as biomarkers for early detection and diagnosis of breast cancer.