Squamous cell carcinoma(SCC)of the breast is rare and its clinicopathological features have not been fully elucidated. We report a patient with SCC of the right breast who underwent surgical resection. A 51-year-old woman was admitted to our hospital because of a right breast tumor. A round tumor with an irregular surface measuring about 3.0×2.5 cm was palpable in the ACarea of the right breast. No abnormal data were observed on laboratory examination, including tumor markers such as carcinoembryonic antigen(CEA), cancer antigen 15-3(CA15-3), breast cancer antigen 225(BCA225), and SCC antigen. Mammography showed a mass with spiculation measuring 2.7×1.7 cm. Ultrasonography also demonstrated a hypoechoic solid tumor with an irregular surface, measuring 2.6×1.6 cm. The pathological diagnosis of a needle biopsy specimen was a mixed type of SCC. We performed a typical right mastectomy with axillary and supraclavicular lymph node dissection. The tumor size was 2.8×1.8 cm. SCC was histologically diagnosed. There was partial invasion to other tissues. The dissected lymph nodes were not involved by carcinoma. Hormone receptors(estrogen and progesterone)and HER2 results were negative. The pathological Stage was II A(T2, N0, M0). The patient refused chemotherapy. However, her condition remains satisfactory without recurrence 2 years after surgery.