Aggressive behavior, resistant to pharmacological and psychological treatment, is observed in some cases of autism. The main objective of this study is to analyze the efficacy of deep brain stimulation (DBS) for aggressive behavior in severe autism The effectiveness of DBS was analyzed in a clinical follow-up of 5 autistic patients, with impaired functional activity and refractoriness to psychopharmacological and behavioral treatment. The patients were examined in medical meetings and evaluated by experienced professionals using the Overt Aggressiveness Scale (OAS), before surgical implantation and after 6, 12 and, 18 months of follow-up. Student's t-test analyses were performed to assess changes in aggressiveness scores. The effect size of surgical intervention on patients' OAS performance was estimated Before the intervention, patients scored very high on the aggressiveness scale. In the subsequent medical controls, a clinically and psychometrically significant decrease in aggressiveness and self-injury symptoms was observed. These data were confirmed by the parents up to 18 months of follow-up. Very large effect sizes were obtained in favor of DBS In this case series, DBS significantly reduced aggressiveness and self-injury, favoring functionality, social adaptation of the patients, and improving the quality of life of the family. We believe that DBS may be a viable treatment option.