Purpose: to sudy the hearing and speaking abilities of children after cochlear implant. Methods:the cross section study evaluated the hearing and speaking of 30 cochlear implant (CI) recipients at National ENT Hospital from 9/2012 to 4/2014, who were the children having pre-language bilateral severe to profound hearing loss. Pure tone hearing test were carried out to assess the Pure Tone Average (PTA) of 3 frequencies 500, 1000, 2000Hz before the operation and Pure Tone Average (PTA2) of 4 frequencies 500, 1000, 2000, 4000Hz post operation. Hearing and speaking of the children were assessed by the Preschool Language Scale -5 (P LS-5) that was translated and revised In Vietnamese. Results: Pre-operative PTA showed that 28 patients (93,3 percent) had bilateral profound hearing loss
only 2 patients had severe hearing loss in one ear and profound hearing loss in other ear. Post- operative showed that 100 percent PTA2 in the ear of CI was inferior 45dB in which PT A2 from 25dB to 35dB occupied 70,1 percent. The hearing of 4 children (13,6 percent) and the speaking of 3 children (10 percent) acquired the normal range of hearing and speaking of normal hearing children. Conclusion: When the child is older than 1 year, the younger child gets CI the better outcome is expected, but it depends on the auditory verbal therapy as well.