The purpose of the study was to examine alternating motion rate and its variability in children with childhood apraxia of speech (CAS) compared to typically developing children. Six children with CAS aged 9-12 years old and 10 children who were age-matched participated in the study. This study measured tokens per second and variabilities of the rates during the production of /$p^*$ a/, /$t^*$ a/, and /$k^*$ a/. For variability measures of the rates, each participant was asked to repeat speech tasks three times and the average value of the rates and its standard deviation were obtained. The results revealed that the CAS group showed slower rate only at /$k^*$ a/ than the control group. The CAS group exhibited greater variability of AMR at all the tasks than the control group. The results suggested that variability of AMR might be a more distinctive speech feature to children with CAS than the rate of the speech task.