The present work assessed Mandarin sentence understanding when the electric and acoustic portions are not temporally aligned in simulated combined electric-and-acoustic stimulation (EAS). A relative time shift was added between the electric and acoustic portions, simulating the temporal misalignment effect in EAS processing. The processed stimuli were played to normal-hearing listeners to recognize. Experimental results showed a significant decrease of the intelligibility score caused by the temporal misalignment in the two portions of EAS processing, suggesting the need to avoid temporal misalignment in EAS. The preceding acoustic-portion more significantly decreased the understanding of EAS-processed Mandarin stimuli than the preceding electric-portion.