Objective To investigate the expression of epidermal growth factor receptor (EGFR) and C-erbB-2 proteins in breast cancer, and to search the relation between micrometastasis in bone marrow and the above facts. Methods SABC immunocytochemical assay for EGFR and C-erbB-2 proteins were made on paraffin embedded section. The statistical analyses were performed using chi-square test. Results Overall, 42.9%of the tumors were EGFR proteins positive.C-erbB-2 proteins were positive in 31%of the tumors. The positivity of both EGFR and C-erbB-2 proteins was significantly connected to that of micrometastasis in bone marrow. The positivity of EGFR proteins was not related to that of C-erbB-2 proteins. The follow-up period of 26 patients was 60 months. The overall survival was worse in patients with EGFR, C-erbB-2 proteins positive tumors compared with EGFR, C-erbB-2 proteins negative tumors. Conclusion EGFR, C-erbB-2 proteins are significantly related to micrometastasies in bone marrow. Multivariate analyses show that both EGFR and C-erbB-2 proteins positive are two key prognostic factors in breast cancer patients.