Developmental abnormalities of breast can lead to formation of ectopic breast tissue which may present as polymastia or polythelia or in form of swelling along the milk line. Ectopic breast tissue can also develop pathological changes similar to normal located breast tissue. This report is about a case of fibroadenoma developing in ectopic breast tissue of axilla. A thirty-four-year-old female presented with painful swelling in right axilla for 2 years and was diagnosed with fibroadenoma of axillary tail of right breast. Excision biopsy of the swelling confirmed the diagnosis of fibroadenoma. Fibroadenoma must be considered for any axillary swelling along with other differential diagnoses like lymphadenopathy, carcinoma arising from ectopic breast tissue, lipoma, sebaceous cyst, tuberculosis, vascular lesions, cutaneous malignancies or secondaries in lymph nodes. Ectopic breast tissue should be subjected to similar evaluation and screening as is recommended for normally located breast tissue. The patient should also be evaluated for possibility of kidney and urinary tract malformations.