A 59-year-old woman presented to our hospital with a mass in her left breast. Mammography and ultrasound showed a 9 ×11×12mm mass in her left breast, and left axillary lymph adenopathy. Core needle biopsy and pathological examination confirmed the diagnosis of ER-negative, PgR-negative, HER2-positive invasive ductal carcinoma with axillary lymph metastasis. Dynamic computed tomography(CT)and bone scintigraphy showed no metastasis. A diagnosis ofbreast cancer with stage II A(T1N1M0)was made, and we started neoadjuvant chemotherapy. After 4 cycles of chemotherapy with 5-fluorouracil/ epirubicin/cyclophosphamide in 3-weekly cycles, we administered combination chemotherapy ofnab -paclitaxel and trastuzumab in 3-weekly cycles. After 7 months, the tumor disappeared and the axillary lymph node got significantly smaller. We performed nipple-sparing mastectomy/axillary lymph nodes dissection/tissue-expander placement. The pathological examination ofthe resected tumor confirmed a pathological complete response(pCR). The patient was treated with implant reconstruction and adjuvant therapy. One year has passed after the surgery, and no significant problem has been observed.