Abstract : Epidemiological studies indicated that estrogens are one of breast cancer risk factors and most established risk factors for breast cancer in humans probably act through hormone-related pathways. This study included 50 breast cancer women, 25 women with benign tumor and 25 healthy controls. Sera of patients and controls were assessed for the level of estradiol using estradiol ELISA kit. The estradiol level was significantly decreased in postmenopausal women than premenopausal women for all study groups. However, there was no significant difference of estradiol level between all study groups in pre or post menopause.