Abstract : This review illustrates the relationship between biomarker and breast cancer and their molecular aspects which referring to both drugs and therapies. Even though, various prediction models have been constructed for breast cancer therapy, established clinopathological factors are not sufficient for clinical decision making particular regarding adjuvant chemotherapy. Some of the key decisions in the current management of breast cancer involve the need for prognostication; which is especially important in identifying patients whose prognosis is so favorable or patients whose prognosis is poor with conventional treatment as to warrant consideration of more aggressive investigational therapies. Several major programs have been organized to facilitate the validation and assessment of cancer molecular marker alongside the established “standards of care” for cancer diagnosis and treatment. Despite their successes, it is now commonly accepted that molecular marker have independent predictive power for disease predisposition, early detection, cancer staging, therapy selection, identifying weather or not a cancer is metastatic, therapy monitoring, assessing prognosis and advanced in the adjuvant setting. In this review, markers have been discussed essentially by highlighting the molecular aspects and referring to both drug and therapies, only as overviews.