Objective：To explore the expression and clinical significance of p53, C-erbB-2, p21WAF1 and CDK4 in breast cancer tissue. Methods：The level of p53, C-erbB-2, p21WAF1 and CDK4 were detected with immunohistochemical staining method in 120 breast tissues species. The relationship between p53, C-erbB-2, p21WAF1, CDK4 and some clinicopathologic factors were analyzed. Results：P53, C-erbB-2, p21WAF1, CDK4 were mostly expressd in nucleus with rates of 53.3%，63.3%，58.3%，41.6% respectively. The expression level of p53, C-erbB-2 was significantly correlated with histological grade（P < 0.05） and axillary lymph node metastases（P < 0.01）. The p21WAF1 expression was related with lymph node metastasis（P < 0.01）, while not related with clinicopathologic characteristics such as histological grade, PR and ER status（P > 0.05）. The expression of CDK4 was correlated with histological grade（P < 0.01）. and lymph node metastasis status（P < 0.01）,while not correlated with PR and ER status（P > 0.05）. Conclusion：The gene products of p53, C-erbB-2, p21WAF1, CDK4 play a key role in the oncogenesis and development of breast cancer. Their expression could be useful indexes to assess the malignant level and clinical prognosis of breast carcinoma. The expression of p53 and axillary lymph node metastases may be dependent prognostic indicators of operative survival for patients with breast cancer. The combined use of the above markers may be helpful in making a better estimation of prognosis.