Objective To investigate the clinical implication on expression of HLA class I in breast cancer tissures.Methods The expression of HLA class I in 271 patients with breast cancer that underwent radical operation was examinedby using immunohistochemically， and the correlation between the expression of HLA class I and clinicalpathological characteristics and prognosis of breast cancer was analyzed. Results The b positive expression of HLA class I in breast cancer tissures was observed in 92 patients （33.9%）， the expressions of HLA class I in 179 patients （66.1%）were downregulation. The expression of HLA class I expression in breast cancer tissures was significantly associated with the axillary lymph node metastasis， TNM stage （P＜0.05）， other lymph node metastasis， and vascular invasion （P＜0.05）. The disease free survival rate of patients with positive expression of HLA class I was higher than that expression downregulation of HLA class I （P＜0.05）. Conclusion The examination of HLA class I expression is useful for the prediction of tumor progression and recurrent risk of breast cancer via the antitumor immune system.