Gastrointestinal problems have been documented in Autism Spectrum Disorder (ASD). Studies have found that these disturbances may be associated with an altered gut microbiome in ASD. Furthermore; in ASD these alterations are implicated in increased gut permeability; or “leaky gut”, which allows bacterial metabolites to cross the gut barrier which may affect neurodevelopment during early childhood in susceptible subjects by way of gut-brain axis. In our review we will discuss the interaction of gut microbiota and brain development in ASD and the signaling mechanisms underlying this interaction. We will also explore the potential for treatment of ASD by targeting the microbiome with probiotics. Finally; this paper will attempt to provide significance to the aggregation of the research in this area of research; providing our interpretations and assessments of future of this field