Abstract: P₅₃ gene is a importent tumor supprossor, its abnormal expression were closely correlated with carcinogenesis and development of the tumor cells. In this report,we determined expressive status of P₅₃ gene for 58 paraffinembedded specimens of breast tumor by ABC immunohistochemical techniec. The results showed that abnormal expression of P₅₃ gene was found in 23 of as (39. 7% ) specimens, and relativity significantly to differentiation degree of the tumor, region lymph node metastasis, sex hormone receptor and, abnormal expression of P₅₃ gene associated with after surgery 5-year survival rate of patients with breast tumor.