Objective:To investigate the expression and the significance of a group of metastasisassociated proteins in invasive ductal breast carcinoma (IDC).Methods :Tissue microarray containing 247 IDC specimens was constructed. The expressions of αB crystallin, CD44v6, MMP2 and TIMP2 were detected by immunohistochemistry, and the relation between the expression of these proteins and the clinicopathologic character was analyzed.Results:(1) The expression rates of αB crystallin, CD44v6, MMP2 and TIMP2 in IDC were 70.0%, 61.5%, 57.5% and 57.1% respectively, and significantly higher than those of normal breast tissues (P＜0.001); (2) Univariate analysis indicated that there were significant positive correlations between the expression of αB crystallin, CD44v6, MMP2 and lymph node metastasis of breast carcinomas(r value is 0.317，0.623 and 0.705 respectively), and significant negative correlations with TIMP2 (r=-0.532). (3) Logistic stepwise regression analysis indicated that the expression of αB crystallin, CD44v6, MMP2 and TIMP2 were significantly related with the lymph node metastasis, and the predicted percentage for the metastasis was 89.5% by these four proteins together.Conclusions:The expressions of αB crystallin, CD44v6, MMP2 and TIMP2 was significantly correlated with the metastasis of IDC. It is possible to estimate the metastatic potency of breast carcinoma by testing metastasisassociated proteins.