<p><i>Objective</i>: This study explored tone production, tone perception and intelligibility of produced speech in Mandarin-speaking prelingually deaf children with at least 5 years of cochlear implant (CI) experience. Another focus was on the predictive value of tone perception and tone production as they relate to speech intelligibility. <i>Design</i>: Cross-sectional research. <i>Study sample</i>: Thirty-three prelingually deafened children aged over eight years with over five years of experience with CI underwent tests for tone perception, tone production, and the Speech Intelligibility Rating (SIR). A Pearson correlation and a stepwise regression analysis were used to estimate the correlations among tone perception, tone production, and SIR scores. <i>Results</i>: The mean scores for tone perception, tone production, and SIR were 76.88%, 90.08%, and 4.08, respectively. Moderately positive Pearson correlations were found between tone perception and production, tone production and SIR, and tone perception and SIR (<i>p</i> < 0.01, <i>p</i> < 0.01 and <i>p</i> < 0.01, respectively). In the stepwise regression analysis, tone production, as the major predictor, accounted for 29% of the variations in the SIR (<i>p</i> < 0.01). <i>Conclusions</i>: Mandarin-speaking cochlear-implanted children with sufficient duration of CI use produce intelligent speech. Speech intelligibility can be predicted by tone production performance.</p