Autism, also known as Autism Spectrum Disorder (ASD), is a serious neurodevelopmental disorder that has attracted considerable attention owing to its increasing incidence worldwide. In recent years, the role of the Gut-Brain Axis (GBA) in ASD development has attracted much attention. The Gut-Brain Axis (GBA) is a bidirectional communication system between the gut and the brain and is a key component of the gut microflora, which is closely related to ASD. Studies have shown that the composition of the gut microbiota in patients with ASD differs significantly from that in healthy individuals, such as changes in the abundance of specific bacterial genera, reduction in beneficial flora, and changes in the abundance of fungi, which are affected by a variety of factors such as diet, geography, and age. Changes in gut flora can trigger metabolite abnormalities, increased intestinal permeability, immune system abnormalities, and abnormalities in the HPA axis and neural pathways, which in turn affect the development of ASD. In addition, gut flora can be involved in the expression of ASD related behavioral phenotypes by affecting the levels of neurotransmitters such as 5-hydroxytryptamine, ?-aminobutyric acid, histamine, and dopamine. In this regard, interventions based on the gut-brain axis, such as probiotics, dietary therapies, and fecal microbial transplantation, have shown potential to improve ASD symptoms but still face challenges, such as insufficient sample size and lack of clinical validation. This paper aims to review the mechanisms of the gut brain axis in ASD and evaluate existing intervention strategies to provide new ideas and directions for the early diagnosis and personalized treatment of ASD.