Autism SPECTRUM disorder (ASD) is a neurodevelopmental condition of heterogeneous etiology, categorized by social communication deficits, repetitive or restrictive behaviors and interests. Epidemiological studies have shown that the incidence of autism is increasing and its treatment is vitally important. Therefore, the purpose of this study was to investigate the effectiveness of vitamins, minerals, essential fatty acid, and a gluten-free and casein-free (GFCF) diet as a treatment for children with ASD. The existing nutrition and dietary therapies were investigated and their effects on ASD symptoms were discussed briefly. Reviewing the studies showed that nutritional and dietary therapies can improve the core symptoms of ASD. This review investigated the importance of vitamins, minerals, essential fatty acids and GFCF diet. Recent studies have suggested that nutrition and dietary supplements may play an active role in improving symptoms of ASD. . .