Objective: To study influence of NAC on the expression of Cerb-B2 in patients with breast cancer and its correlation with clinical curative effects.Methods : From 2010 to 2012 the Cerb-B2 expression before and after NAC of 70 patients with breast cancer were detected by immunohistochemistry. The neo-adjuvant chemotherapy regimen (TT regimen )was taxotere 70mg/m2 in day one, pirarubicin 60 mg in day one for 21 days one cycle. After 2-4 cycles, the patients were underwent surgical operation. The changes of Cerb-B2 expression before and after NAC were compared and its correlation with NAC’s clinical curative effects was analyzed. Results: Among the 70 patients, 13 cases（group A）kept the expression of Cerb-B2 overexpression, 16 cases （group B） showed a transformation of the expression of Cerb-B2 from overexpression to non-overexpressed, 7 cases （group C）showed a transformation of the expression of Cerb-B2 from non-overexpressed to overexpression, 34 cases（group D）kept the expression of Cerb-B2 non-overexpressed, with statistical alteration for Cerb-B2 status due to NAC(P<0.05), and non-statistical diversity for therapeutic effects between Cerb-B2 overexpression and non-overexpressed patients (P=1.0) and between the four groups (P=0. 589). Conclusion: NAC can change the Cerb-B2 expression status in patients with breast cancer, but there is no statistically related to clinical performance of NAC, and there is no relationsipe between the Cerb-B2 expression status and NAC neither.