Isolated tuberculosis of the breast is rare, even in developing countries where pulmonary and other extrapulmonary manifestations are endemic. The reported incidence of tuberculous mastitis is 0.1% of all reported breast lesions worldwide, whereas in developing countries, it constitutes approximately 4.5% of surgically treated breast disease. Primary breast tuberculosis is most often seen in women between the ages of 20 and 50 years, is rarely bilateral, and may coexist with carcinoma. It presents a difficult diagnostic dilemma, both clinically and radiographically. We describe a case of primary breast tuberculosis in a low-risk patient. Mammography and sonography were performed. The diagnosis was based on pathologic examination after sonographically guided core-needle biopsy. Nonspecific radiologic features and a review of the relevant literature are presented.