The concurrent rise in the prevalence of autism and youth suicide has drawn public health and professional attention. The renaissance of psychedelics in psychiatry occurred in the early 21st century and may suggest a hope for the therapeutic effect of psychedelics in autism and suicide. The psychedelics' molecular entities are the compounds that modulate the serotoninergic and glutamatergic systems, which play a crucial role in the pathomechanisms underlying autism and suicide. This systematic review comprehensively discussed the prevalence trends of autism and youth suicide globally and in Taiwan and discussed an association between autism and suicidality based on the 21st century clinical and preclinical literature. Furthermore, this review proposed a possible neurobiological connection between autism, suicide, and psychedelics. Finally, this review discussed the potential therapeutic applications of psychedelics in autism and youth suicide.