Cholesterol granuloma of the breast is a very rare benign disease with clinical and imaging features that are often indistinguishable from cancer preoperatively. We report a case of breast cholesterol granuloma accompanied by cancer. The patient was a 78-year-old woman who complained of a lump in her right breast. Mammography and ultrasonography showed a well-circumscribed mass. Fine needle aspiration cytology showed many cholesterol crystals and inflammatory cells without malignancy. With a diagnosis of cholesterol granuloma, tumor extirpation was performed. Histopathologic examination revealed cholesterol granuloma together with breast cancer, and additional partial mastectomy was subsequently performed. It is noted that breast cholesterol granuloma could be accompanied by cancer.