Autism spectrum disorder (ASD) is a neurodevelopmental disorder with an increasing frequency, manifested by functional disorders in social communication and social interaction, limited interests, and repetitive behaviors. The etiology of autism spectrum disorder has not yet been fully elucidated and there are many areas that need further study. Increasing studies have shown that disruptions in synaptic functions are critical in the onset of ASD. Glial cells have a role in the regulation of synaptic functions. In ASD, changes are seen in the number of neurons and glia cells in the affected cerebral cortex, and these changes cause dysregulation in synaptic functions and affect behaviors. Studies provide information about the role of glia cells in the pathophysiology of ASD, but more data is needed on the relationship between ASD and glia cells. In this review, the importance of glial cells in the etiopathogenesis of ASD and studies will be discussed.