Objective: The main goal of this paper was to establish the prevalence of autism spectrum disorders (ASD) in children that were processed in the Clinical Hospital Centre Rijeka from year 2010. to 2014., to see the differences between the sexes, mean age of diagnosing the state and to determine how many of the children had an EEG result and a neuroimaging examination as well as to define which ones had a child’s psychiatrist or psychologist’s follow up. Materials and methods: The data of 43 children have been retrogradly collected and analyzed. Research criteria determined that the year of diagnosing PAS had to be within the study period and that the diagnosis had to be confirmed by a pediatrician, psychiatrist or a psychologist. Results: The research shows that the number of children with a confirmed ASD diagnose has grown. Periodic prevalence is found to be 5,37/10000. The ratio of affected boys and girls is 5:1. The mean age of the children at the time of diagnosis was 4 years. 55,81% of the children had a result of a neuroimaging method, 65,2% had an EEG result and 92,02% of the children are under supervision of a child’s psychologist or a psychiatrist. Conclusion: The number of ASD affected patients has grown in the last couple of years, with a higher dominance in boys. In order to intervene properly and to have a better outcome the mean age of the children at the time of diagnosis should be lower. Children suffering from ASD can be victims of stigmatization and violence which needs to be prevented. People with ASD should be given support and opportunities because, with their special abilities, they might be a new variant within human species.