A 76-year-old postmenopausal woman presented with a bloody attachment on the left nipple. She had a 3 cm-sized tumor in her left breast. Mammography showed a spiculated irregular mass. Ultrasonography showed a 38 mm, low echoic mass with an irregular border. Core needle biopsy examination indicated apocrine carcinoma of the breast, ER(-), PgR(-), and HER2(-). An overall examination showed no distant metastasis. We diagnosed her with apocrine carcinoma of the breast(T2N0M0, cStageⅡA). We performed total mastectomy with sentinel lymph node biopsy. The postoperative histopathological examination revealed apocrine carcinoma without lymph node metastasis. The patient recovered uneventfully and was discharged 8 days after the surgery. She has not experienced any recurrence for 1 year and 7 months after the surgery.