PURPOSE: This study was prospectively carried out to determine the concordance between the immunohistochemical assay (IHC) and the enzyme immunoassay (EIA) assessing estrogen receptor (ER) and progesteron receptor (PR) in breast cancer tissues. MATERIALS AND METHODS: Breast carcinoma tissues were obtained from 36 patients. Hormonal receptors were determined by IHC assay using polyclonal antimouse antibody and by EIA. The concordance between two methods and the concordance according to in age, tumor size, stage, and lymph node metastasis of breast cancer patient were analyzed. RESULTS: The concordant rate of ER status was 88.9% between IHC and EIA. ER-IHC(+)/EIA(-) were 3 cases and ER-IHC(-)/EIA(+) was 1 cases. ER-positive was 63.9% in IHC and 53.8% in EIA. The concordant rate of PR status was 86.1% between IHC an EIA. PR-IHC(+)/EIA(-) were 4 cases and PR-IHC(-)/EIA(+) was 1 cases. PR-positive was 61.1% in IHC and 52.8% in EIA. There was high concordance (76.2-100%) in age, tumor size, stage, and lymph node metastasis. CONCLUSIONS: There was high concordance between immunohistochemical assay and enzymeimmunoassay determining estrogen and progesteron receptors in the breast cancer. The IHC assay appears to be a resonable substitute for the EIA to determine hormonal receptors.