One patient with sebaceous nevus of Jadassohn is presented.This lesion is considered a hamartoma, because it is caused by benign hyperplasia of sebaceous glands.Most common location is on the scalp and less frequently on the face, trunk and extremities, with a low risk to malignant neoplasia.The lesion may appear from birth.When patients get to puberty, develop into different kinds of tumors.Treatment is surgical excision along prepuberal age.