Dermal thymus in bilateral sides of neck is very rare, probably unique anomaly of branchio-oculo-facial syndrome (BOF). We report a case of BOF with cleft lip and non-healing erosions on bilateral sides of neck. The thymus of neck in our case showed unusual clinical course that appeared at 1 year and half of age after the repair of cleft lip deformity. The lesions of neck were completely excised, and the histopathologic examination for neck lesion confirmed ectopic dermal thymus. Ectopic thymus can be excised completely after careful evaluation of haematologic, immunologic status if normal thymic shadow cannot be identified on chest X-p.