Autism spectrum disorder (ASD) is a chronic neurodevelopmental disorder with onset in childhood, characterised by core clinical features including impaired social interaction and communication, as well as restricted and repetitive behaviours and interests. Its pathogenesis involves interactions between genetic and environmental factors, while the specific biological mechanisms remain incompletely elucidated. Recent studies have demonstrated that mitochondrial structural and functional disorders may be a key contributor to the pathogenesis of ASD. As the primary organelles responsible for energy production, mitochondria play a crucial role in neurodevelopmental processes, including neurogenesis, neuronal migration, synapse formation, and synaptic pruning. Current research has identified widespread mitochondrial-related abnormalities in individuals with ASD, including mitochondrial DNA mutations, elevated oxidative stress levels, and metabolic dysregulation. Mechanistic studies indicate that mitochondrial dysfunction, including energy metabolism defects and mitochondrial dynamics imbalances, collectively impair synaptic plasticity and abnormal neural circuitry, ultimately leading to the core behavioural manifestations of ASD. Based on the aforementioned findings, researchers have further explored various potential intervention strategies targeting mitochondria, including gene editing, mitochondrial transplantation, antioxidant therapy, metabolic reprogramming, and modulation of the gut-brain axis through microbiome-based interventions. This article hypothesizes that mitochondria may serve as a critical integrative hub linking genetic susceptibility and environmental risk factors. Their structural and functional dysfunctions not only provide a biological basis for the neurodevelopmental abnormalities characteristic of ASD but also point the way toward future interventions targeting the core pathophysiological mechanisms of ASD.