Introduction: Incidence of breast cancer in women varies with age, mammary gland mass and exposure to endogenous and exogenous hormones. Breast cancer grows within a hormonal milieu which plays an important role in its development. Aim: The present study was planned to assess circulating hormone (serum estrogen (E2), progesterone, and testosterone, FSH, LH and AMH) levels in breast cancer patients and to elucidate the influence of chemotherapy on these hormones by comparing them with age matched healthy control women. Materials and Methods: This prospective study was conducted in the Department of Biochemistry in collaboration with Department of Radiotherapy in PGIMS, Rohtak. The subjects were divided into three groups: Group I (control group): Healthy age matched female volunteers with no prior history of breast cancer (n=30), Group II (study group): Newly diagnosed confirmed cases of breast cancer (n=30) and Group III (study group): Postchemotherapy group (n=30; Group II patients who had undergone chemotherapy). Serum Estrogen (E2), Progesterone, Testosterone, FSH, LH and AMH levels were estimated in healthy controls and patients before and after chemotherapy. Result: In the present study, E2 levels were significantly decreased while progesterone levels were significantly increased in group II and group III when compared with group I (p<0.001 and p<0.001 respectively). There was no significant change in Testosterone, FSH and LH levels in between study group (group II and group III) as compared with group I (p>0.05). AMH levels were also significantly decreased in both group II and group III when compared with group I (p<0.001). Conclusion: Present study concluded that AMH could be a valuable marker in these patients as it provides the exact knowledge of time by which the damage to granulosa cells and growing follicles occurs resulting in decreased ovarian reserve (OR); this is of great importance for the decision regarding the reproductive planning and optimal adjuvant hormonal treatment for women.