PURPOSE: To verify the performance of children with and without speech sound disorder in oral motor skills measured by oral diadochokinesia according to age and gender and to compare the results by two different methods of analysis. METHODS: Participants were 72 subjects aged from 5 years to 7 years and 11 months divided into four subgroups according to the presence of speech sound disorder (Study Group and Control Group) and age (<6 years and 5 months and >6 years and 5 months). Diadochokinesia skills were assessed by the repetition of the sequences 'pa', 'ta', 'ka' and 'pataka' measured both manually and by the software Motor Speech Profile®. RESULTS: Gender was statistically different for both groups but it did not influence on the number of sequences per second produced. Correlation between the number of sequences per second and age was observed for all sequences (except for 'ka') only for the control group children. Comparison between groups did not indicate differences between the number of sequences per second and age. Results presented strong agreement between the values of oral diadochokinesia measured manually and by MSP. CONCLUSION: This research demonstrated the importance of using different methods of analysis on the functional evaluation of oro-motor processing aspects of children with speech sound disorder and evidenced the oro-motor difficulties on children aged under than eight years old.