Cystic lymphangiomas commonly occur in childhood, but breast involvement is an extremely rare entity that tends to be more common in adults, with only a few cases reported in children. We describe a 6-year-old boy who presented with a lump in the left breast that measured 4.5 x 3.5 x 2.5 cm. A local excision was performed, and a diagnosis of cystic lymphangioma was confirmed. There was no recurrence of the lesion after 18 months after surgical excision. A brief case description and review of the relevant literature is presented.