Squamous cell carcinoma is a rare type of breast malignancy. Three patients are described. The clinical features, histologic findings, and postoperative course are described. All three patients had operation, and two received chemotherapy and radiotherapy. Two patients are well 2 and 6 years postoperatively, and the third patient died from extensive metastases within 34 months after radical mastectomy without postoperative chemotherapy and radiotherapy.