Abstract: Objective To investigate the expression of P-cadherin in breast cancer， and analyze its relationship with clinicopathological characteristics. Methods The expression of P-cadherin in 106 cases of breast cancer specimens and 30 adjacent normal tissues were detected by immunohistochemical method（SP），and the relationship between its expression and clinical characteristics were analyzed. Results The positive expression rates of P-cadherin in breast cancer and adjacent normal tissue were 42.5％ and 13.3％ respectively， and the difference was statistically significant（P＜0.05）. P-cadherin expression in breast cancer was correlated with TNM stage，histological grade， lymph node metastasis, HER-2 situation， ER and PR（P＜0.05）， but not correlated with age and tumor size（P＞0.05）. ConclusionThe over-expression of P-cadherin in breast cancer may relate to the level of malignancy and poor prognosis.