Recent studies show that oxidative stress has an important role in the etiology of autism. In our study, Nrf2, which is the main regulator of cellular antioxidant response, and Keap1 and Gsk-3[beta], which are the main proteins that regulate this pathway, were compared between children with autism and healthy controls. To the best of our knowledge, our study is the first in which Nrf2, Keap1 and Gsk-3[beta] levels were evaluated together in children with ASD. In our study, Nrf2 level was found to be lower and Keap1 level higher in children with autism. Although GSK-3[beta] is increased in many psychiatric and neurodegenerative diseases, it was found to be low in the autistic group in accordance with the literature. In conclusion, considering the versatile modulation of the Nrf2 pathway, this article does not provide any mechanistic insight into the pathway, but it suggests that Nrf2, Keap1 and Gsk-3[beta], which have central roles in oxidative stress, may play a role in the pathophysiology of autism.