Children with congenital atresia of the external auditory canal require an early assessment of hearing and a determination of the degree of atresia and associated pathology by polytomography and/or high-resolution CT scanning. We analyzed the otologic findings in 302 ears (239 patients) with severe atresia of the external auditory canal. Eighty-seven primary or revision surgeries were performed. Fifty-three percent obtained a residual conductive deficit of 20 dB or less. Lateralization of the tympanic membrane graft was the primary cause of failure in obtaining good hearing results. The use of split-thickness skin graft instead of a full-thickness skin graft to cover the reconstructed external canal has decreased the incidence of restenosis and revision surgery.