From April, 1990 to July, 1993, 351 patients had received medical examination at our surgical department, who complained of an abnormal condition in their breast. Abnormal nipple discharge was found in 34 out of 351 patients. On such cases, cytological diagnosis was firstly performed and ductography was also performed as possible. As a result, microdochectomy was performed on the following cases, whose secretory fluid was bloody, or who revealed as class III or more in cytological diagnosis, and whose secret continued a couple of month even the patient was ranked class II or less. We had four cases of microdochectomy and histological diagnosis on them indicated three intraductal papillomas and one duct papillomatosis. Intraductal papilloma included one class I and two class III and duct papillomatosis was class II in cytological diagnosis respectively. We concluded that the microdochectomy is a useful method for diagnosis and treatment of nipple discharge and also is excellent in cosmetic view.