Gut dysfunction and microbial dysbiosis comorbidities are of particular interest in recent autism research, as gastrointestinal distress is present in up to 90% of autism spectrum disorder cases and therefore may play a key role in the pathogenesis of this disorder. This scoping review aims to integrate the results of studies conducted in the past 6 years examining the association between gut microbiota and autism spectrum disorder, specifically with regard to the characterization of autism spectrum disorder microbiota and potential therapeutic interventions. Studies related to the gastrointestinal microbiome of subjects with autism spectrum disorder were identified through PubMed, SCOPUS, PsycInfo, and Google Scholar databases. Studies were screened and selected based on defined inclusion and exclusion criteria; 19 studies were included. Research continues to report differences between microbiota of individuals with autism spectrum disorder and controls; however, the types and abundances of bacteria present remain inconsistent. Promising treatment interventions for autism spectrum disorder, including special diets, dietary supplementation, and of particular interest, microbiota transfer therapy, are also being explored. Research regarding the link between gut microbiota and autism spectrum disorder renders exciting results; however, it is still in its infancy of investigation. Rigorous methodologies are required to support and strengthen the reliability of existing results, and to further our understanding of the pathogenesis of autism spectrum disorder.