Sixty-nine cases of axillary accessory breast tissue, including its physiologic changes and pathologic lesions, were diagnosed by fine needle aspiration cytology. The age of the patients ranged from 13 to 40 years, with a median of 25, and all were female. The cases presented with swellings in the left axilla in 16 cases, right axilla in 30 cases and both axillae in 23 cases. The common clinical diagnoses included accessory breast tissue (23.2%), lipomatous lesion (17.4%), lymphadenopathy (18.8%) and swellings not otherwise specified (30.4%). In 8.8% cases two of the possibilities were considered. The cytodiagnoses included axillary accessory breast tissue (47 cases), axillary breast tissue with pregnancy or lactational changes (15), cystic disease (4) and fibroadenoma (3). One of the cystic disease cases showed granulomatous inflammation. Although no case of carcinoma in axillary breast tissue was diagnosed during the study period, there were two cases of malignancy in axillary swellings (diagnosed as metastatic carcinoma) when no primary was detected in the breasts.