Autism spectrum disorder is a set of neurodevelopmental disorders in terms of prevalence, morbidity and impact to the society, which is characterized by intricate behavioral phenotype and deficits in both social and cognitive functions. The molecular pathogenesis of autism spectrum disorder has not been well understood, however, it seems that PI3K, AKT, and its downstream molecules have crucial roles in the molecular pathogenesis of autism spectrum disorder. The PI3K/AKT signaling pathway plays an important role in the regulation of cell proliferation, differentiation, motility, and protein synthesis. Deregulated PI3K/AKT signaling has also been shown to be associated with the autism spectrum disorder. Discovery of molecular biochemical phenotypes would represent a breakthrough in autism research. This study has provided new insight on the mechanism of the disorder and would open up future opportunity for contributions to understand the pathophysiology.