Estrogen receptor alpha (ESR1) belong to the nuclear receptor family of ligand-inducible transcription factors. It involves in both proliferation of breast cancer cells as well as in carcinogenesis. Many studies on polymorphisms suggested its correlation with various aspects of breast cancer. The most studied Polymorphisms are SNPs and microsatellites lying within intron one of estrogen receptor alpha (ESR1) gene. A possible linkage of ER gene found in families of breast cancer patients, suggested that either the ER gene itself or an adjacent gene may be a risk of breast cancer. These alleles have also been found to be associated with traditional risk factors of breast cancer including age, family history, menstrual cycle, menopausal status, anthropometric measurements (height, weight etc.) and pregnancy history. Estrogen receptor alpha (ER-α) status also plays a role in decisions making for endocrine therapy. This review focuses on association of estrogen receptors α (ESR1) polymorphism with the breast cancer risk. By understanding the frequency of occurrence of ER α polymorphism and associated risk factors may elucidate the breast cancer screening, prevention, and treatments strategies in future.