Recently, vitamin D has been shown to play important roles in the body, beyond its role in bone metabolism, including the regulation of immune and hormonal responses, antioxidant activity, proliferation, and cellular differentiation, and also has a critical role in brain development. Vitamin D deficiency is relarted to increased risk of neurodevelopmental disorders such as Autism Spectrum Disorder (ASD). Although the mechanisms are not fully understood, it seems that there is a relationship between low levels of vitamin D and the risk of Autism Spectrum Disorder. However, to prove this association, prospective Cohort and clinical trial studies with a large sample size are required. In this review, we explored the association between vitamin D and Autism Spectrum Disorder.