Our experience with a total of 7,231 needle aspirates of the breast was reviewed. Ninety-nine cases from the total of 7,231 aspirates studied were from male patients. While an aspiration cytodiagnosis of gynecomastia was made in most of these cases, carcinoma was diagnosed in four cases. Although a clinical distinction between male breast cancer and gynecomastia is often difficult, we found needle aspiration cytology a very useful initial investigation for making this distinction.