Narrow and duplicated internal auditory canal (IAC) is a rare congenital malformation of the temporal bone and usually combined with ipsilateral congenital sensorineural deafness. Congenital narrowing of IAC establishes a relative contraindication to cochlear implantation because it is associated with aplasia or hypoplasia of the vestibulocochlear nerve or cochlear branch. We report a 10-year-old boy with right sensorineural hearing loss. High resolution computed tomography (HRCT) reveals a narrow and duplicated IAC; the IAC is divided into an anterosuperior portion and posterior inferior portion by a bony plate. We present the CT finding and review the literatures in this statement.