The complexity of the embriologic development of the neck and the possible abnomarlies in this process, with the consequent posterior manifestations make necessary the knowledge of the embriologic anatomy of the neck. In the possible manifestations that can be of the anomalies of the development of the branchial archs are the abnomarlies of the first branchial archs. They are, in the anomalies of the development of the branchial archs infrequent and are intimately related with the facial nerve. We present a clinic case of a seven years old boy affected by this pathology and revise its more important aspects.