PURPOSE: To objectively characterize the alterations of autistic children and adolescents as to their severity degree, according to the answers to the Functional Communication Profile - Revised (FCP-R). METHODS: Subjects were 50 children (mean age 7 years 11 months) with diagnosis within the autism spectrum that were assessed according to the FCP-R criteria. Answers were scored and classified according to severity, and the results were statistically analyzed. RESULTS: This group characterization evidenced results that agree with the literature, showing disorders mainly in the areas of language (expressive and receptive), behavior and pragmatics. Individuals without verbal communication also showed speech and fluency disorders. CONCLUSION: The FCP-R was sensitive to characterize the studied population, and even more efficient for individual assessment.