The BRCA2 antibody is a crucial tool in molecular biology and clinical diagnostics, targeting the BRCA2 protein encoded by the *BRCA2* gene. This tumor suppressor gene plays a vital role in DNA repair through homologous recombination repair (HRR), maintaining genomic stability. Germline mutations in *BRCA2* significantly increase lifetime risks of hereditary breast and ovarian cancers (HBOC), as well as pancreatic and prostate cancers. BRCA2 antibodies are widely used in research to study protein expression, localization, and function in cellular models, employing techniques like Western blotting, immunohistochemistry (IHC), and immunofluorescence (IF). Clinically, they aid in assessing BRCA2 protein loss in tumor tissues, which may indicate pathogenic mutations and guide therapeutic decisions, particularly for PARP inhibitor therapies that target HRR-deficient cancers. However, antibody specificity and validation are critical, as cross-reactivity or variability in assay conditions can yield false results. Commercial BRCA2 antibodies vary in clonal origin, epitope recognition, and host species, necessitating rigorous validation with appropriate controls (e.g., cell lines with known BRCA2 status). Ongoing advancements aim to improve antibody reliability, supporting both basic research into DNA repair mechanisms and precision oncology applications.