Materials and Methods: This study has been carried out on 25 cochlear implant children and 25 children with normal hearing in primary school age ranges.Ten pictures were shown to children and statement and question sentences were elicited from them. To investigation of intelligibility, produced sentences were perceptually judgment by seven speech therapists and were scored by five point rating value. Acoustic correlationwere determined using Praat software.    

Results: The results showed that there were significantly difference between two groups in each of acoustic correlations (P<0.05). Intelligibility scores of CI children were significantly lower than ones of NH children (P<0.05). There were significantly correlation between intonation and intelligibility scores, also between intelligibility and duration of implant use (P<0.05).

Conclusion: According to the findings of the present study, cochlear implant children's performance in using of acoustic correlation of intonation is lower than normal hearing peers that results in inappropriately intonation. Inappropriately intonation can be the cause of low intelligibility in cochlear implant children. Thus, intervention of intonation should be considered in treatment program of cochlear implant children.