Granular-cell tumor is an uncommon cause of breast mass in premenopausal women that presents as a painless chronic lump. It mimics infiltrating carcinoma clinically and radiologically. Granular-cell tumor is usually benign, and the treatment is wide local excision. Definitive pre-operative diagnosis helps to avoid unnecessary mastectomy. We present clinical, mamographic, and sonographic characteristics of a benign granular-cell tumor of the breast in a 57-year-old woman.