CDK2 (cyclin-dependent kinase 2) is a serine/threonine kinase critical for regulating cell cycle progression, particularly during the G1-to-S phase transition. It partners with cyclins E and A to phosphorylate key substrates like retinoblastoma protein (Rb), facilitating DNA replication and cell division. Dysregulation of CDK2 activity is implicated in uncontrolled cell proliferation, a hallmark of cancers and other hyperproliferative disorders. CDK2 antibodies are essential tools for studying its expression, localization, and interactions in cellular contexts. These antibodies enable techniques such as Western blotting, immunohistochemistry (IHC), and immunofluorescence (IF) to assess CDK2 levels in tissues or cultured cells, aiding in cancer research and drug discovery. Additionally, they help evaluate CDK2 inhibition strategies, including small-molecule inhibitors or gene silencing, in preclinical studies. While CDK2 was once considered redundant due to overlapping roles with CDK1 and CDK4/6. recent studies highlight its unique functions in specific cancers (e.g., ovarian, breast, and leukemia) and in contexts of CDK4/6 inhibitor resistance. Validated CDK2 antibodies are crucial for ensuring experimental reproducibility, with specificity confirmed via knockout controls or blocking peptides. Their applications extend to biomarker analysis, mechanistic studies of cell cycle checkpoints, and therapeutic development targeting CDK2-driven malignancies.