PURPOSE: To analyze the attribution of mental states in the speech of children within the Autistic Spectrum Disorders, and verify the modification in their vocabulary and phrasal extension, after a period of speech-language therapy. METHODS: Speech samples from the initial Speech-Language Pathology evaluation and follow-up evaluations carried out after six months and one year of speech-language therapy were collected from the records of five children with autism and five with Asperger syndrome, with the aim to characterize their verbal performance and ability of attribution of mental states. Considering only spontaneous emissions, the classes of words nouns and verbs were verified and classified as terms refering to physical and mental states. The comparison between the three evaluations was performed by assessing the significance between the medians of the samples obtained (median test, with significance level at 10%). RESULTS: It was observed an increase in the number of words produced and in the number of words per sentence between the evaluation periods and after a year of speech-language therapy, for children with autism. No differences were found for the attribution of verbs regarding physical and mental states and nouns regarding mental states, for both groups. A decrease in the number of nouns regarding physical states was observed in the autism group. CONCLUSION: The attribution of mental states increased after a period of speech-language intervention, however, with no significant difference; there was an increase in the verbal behavior of children with autism.