Objective To investigate the expression of E-cadherin and matrix metallopeptidase 7(MMP-7)and their significance in basal-like and Her-2 over-expressing breast carcinoma. Methods The protein expression of E-cadherin and MMP-7 were analyzed by immunohistochemical method in 20 cases of basal-like breast carcinoma and 21 cases of Her-2 over-expressing breast carcinoma.Statistical method was used to analyze the clinicopathological performance.Patients were followed up from 6 to 60 months.Results The ratio of basal-like breast carcinoma and invasive ductal carcinoma was 3.4%(20/501).the mean age was 49 years.The mean size of basal-like breast carcinoma(2.1 cm)was smaller than that of Her2 over-expressing breast carcinoma(3.0 cm)(P<0.05).The 5-year survival rate of patients with basal-like breast carcinoma was obviously(40.0%) lower than that of Her-2 over-expressing breast carcinoma (71.4%)(P<0.05),though,the 3-year survival rate was similar between the two groups.The protein expression of E-cadherin was down-regulated and even deficient in basal-like breast carcinoma(P<0.05).The protein expression of MMP-7 was higher in basal-1ike breast carcinoma than that in Her-2 overexpressing breast carcinoma(P<0.05).Conclusion Down-regulated expression of E-cadherin and upregulated expression of MMP-7 may be one of the mechanisms leading to high metastasis of basal-like breast carcinoma.