Tuberculous mastitis is an uncommon disease even in countries where tuberculosis is highly endemic. It typically presents a diagnostic challenge masquerading as carcinoma or other primary disease of the breast. We report the case of a young multiparous Nigerian woman who presented with a tender left breast lump and enlargement of the left axillary lymph nodes for which a provisional diagnosis of carcinoma of the breast was made after clinical and radiological evaluation. The mass was pathologically diagnosed as tuberculous mastitis and anti-tuberculous therapy was instituted although she later absconded. This case shows that TM may present a diagnostic challenge on clinical, radiologic and microbiological investigation. Therefore, a high index of suspicion as well as FNAC and/or histological evaluation of tissue samples remain very important its diagnosis.