A reliable measure for predicting the intelligibility of cochlear-implant vocoded speech is desirable as it can be used to guide the development of new speech coding algorithms for cochlear implants. The present study assesses the performance of several speech quality measures in predicting the intelligibility of cochlear-implant vocoded speech (vocoded English and vocoded Mandarin Chinese). The quality measures are analyzed and correlated with the intelligibility scores of vocoded speech obtained from normal‐hearing listeners in three experiments. The perceptual evaluation of speech quality measure (r = 0.91) and the weighted spectral slope measure (r = -0.87) are well correlated with the intelligibility score. The language effect impacts the performance of objective quality measures in predicting the intelligibility of vocoded speech.