Introduction: A subgroup of patients with autism spectrum disorder (ASD) show self or heteroaggression, dyscontrol episodes, and others are of obsessive-compulsive disorder (OCD) profile; some of them are resistant to medical and behavioural treatment. We describe the long-term outcome in a group of these patients, treated with radiofrequency brain lesions or combined stereotactic surgery and Gamma Knife (GK) radiosurgery. Methods: We reviewed the medical records of 10 ASD patients with pathological aggressiveness and OCD, who had undergone radiofrequency lesions and/or radiosurgery with GK in our institution. Results: The 10 patients had a significant reduction of their symptoms (PCQ 39.9 and 33, OAS 11.8 and 5, CYBOCS-ASD 30.4 and 20), preoperatively and in the last follow-up, respectively; p < 0.005 (in all cases), although all but 2 needed more than 1 treatment to maintain this improvement. Conclusions: We observed a marked improvement in behaviour, quality of life, and relationship with the environment in all our 10 patients after the lesioning treatments, without long-lasting side effects.