Aggressive fibromatosis comprises connective tissue tumours that represent 0.03% of all bodily neoplasms, occurring more often in the abdominal wall, mesentery, and extremities; its location in the breast constitutes a very infrequent type of lesion. Its pathogenesis is diverse and its relationship with augmentation mastoplasty is still unclear. Four cases of aggressive breast fibromatosis following augmentation mastoplasty are reported in this article.