By observing and taking notes on all the processes of teaching autistic children to learn to speak, this research statistics the number of speech structures of 15 Vietnamese autistic children (at three levels) from 3 to 6 years old to evaluate, analysis of component structures developed: one-component utterance, two-component utterances, three-component utterances and complex utterance. The autistic children were observed by using descriptive qualitative study to evaluate and analyze component structure development. This research indicated that there was a considerable difference in the number of utterances between groups of autistic children at different levels. Compared to mild autistic children, the more severely autistic children were, the more structure utterances appeared and the simpler structure utterance used.