Introduction: A number of recent studies have brought attention to the involvement of dietary salt and blood sodium levels in the etiopathogenesis of autism. In our study, by comparing the blood sodium levels of children with autism spectrum disease (ASD) and healthy children, we aimed to shed light on the etiopathogenesis of ASD. Method: We retrospectively analyzed the blood sodium levels obtained from the 4-year follow-up of 84 children (42 with ASD and 42 controls). Results: According to the comparison of blood sodium levels obtained from the 4-year follow-up of children in the ASD and control groups, no significant difference was found between the blood sodium levels of both groups. Discussion: The notion that blood sodium levels influence the progression of autism is novel, and the majority of material on this topic comes from animal trials. The results of the few human-focused studies are controversial. More studies are needed to elucidate the role of blood sodium levels and salt consumption in the etiology of autism.