We studied three patients with Unverricht-Lundborg disease for autistic features along with other clinical features associated with progressive myoclonus epilepsy. We diagnosed this disease based on noise and touch sensitive myoclonus, ataxia, cognitive decline, typical EEG features, normal MRI of the brain and applied Children's Global Assessment Scale and Childhood Autism Spectrum Test to these children. The CGAS score was 35 in two and 50 in one of them. CAST scores were above 15 in all of three of them. Autistic features may be an important clinical feature of this disease. History and physical examination for myoclonus should probably be taken in autistic children.