Breast cancer is the most common neoplasm affecting women in the western world where the incidence is very high and the risk of developing breast cancer is 1 out of 10. The incidence of breast cancer in Iran is much lower; although it is the most common cancer among Iranian women (skin cancer is excluded). For optimum management of these patients, assay of certain biochemical markers is necessary. Breast Carcinomas that express Estrogen Receptor (ER) and Progesterone Receptor (PR) are more likely to benefit from adjuvant hormonal therapy and have a better prognosis, stage for stage, than those with receptor-negative tumors. Clinically; the most useful markers in breast cancer are estrogen and progesterone receptors that are used to predict response to hormone therapy. In the present study the levels of Estrogen Receptor (ER) and progesterone receptor (PgR) were determined in 48 specimens of primary breast cancers using gold standard biochemical assay of steroid hormone receptors by the Dextran-coated Charcoal method (DCC). The commonest histological type of breast tumor was infiltrating ductal carcinoma that accounts for the 81.5 percent of breast cancers. The results demonstrated that 39.6% were ER+, PgR+; 22.9% ER+, PgR-; 31.3% ER-, PgR- and 6.3% ER-,PgR+. In postmenopausal, the incidence of estrogen receptor positive tumors (ER+) was significantly higher than premenopausal (p<0.05). Although the frequency of progesterone receptor positive (PgR+) breast tumors is higher in postmenopausal than premenopausal but the difference is not significance (p>0.05).