Intraductal papillary tumors of the breast exhibit bloody discharge with often no evidence of a palpable tumor, making discrimination between benign and malignant lesions sometimes difficult for pathologists and surgeons. So the technique used in removing the offending ductal system should be fully diagnostic, adequately therapeutic and cosmetically. Microdochectomy has been accepted treatment for intraductal papilloma of the breast. We performed dye-injection microdochectomy on intraductal papilloma of the breast in 15 patients. This procedure utilizes lacrimal probe and 24-gauge medicut that are gently advanced into the offending duct and methylene blue dye is injected to outline the involved duct for easy dissection through a circumareolar incision. Because we could perform dye-injection microdochectomy safely, rapidly and effectively, we think that this procedure is standard treatment of intraductal papilloma of the breast.