Introduction: Isolation of two compounds, tetrahydrocannabinol (THC) and cannabidiol (CBD), contributed to an increased interest in the use of marijuana for medicinal purposes. It was then that research on the effects of marijuana on the course of different diseases began. Aim: The aim of this paper was to analyse the use of cannabinoids in the treatment of children with autism spectrum disorder. Results: There are different methods for cannabinoid administration. Researchers use various preparations with doses ranging between 0.04 mg to 900 mg. Preliminary studies are conducted on animal models, usually in genetically modified mice. Cannabinoids have been found to have a positive effect on social and emotional behaviours of children, as well as to show anxiolytic and antipsychotic effects. Cannabidiol plays an important role in the secretion of vasopressin and oxytocin. Some patients experience adverse effects. Antidepressant and anticonvulsant effects have been observed in patients with neurological and mental disorders. Conclusions: Cannabinoid therapy is not the standard of care in children with autism spectrum disorders, and the doses used vary significantly. There is evidence for the positive effects of cannabinoids in patients with comorbidities. It is possible that cannabinoids have an anxiolytic effect and allow for a reduced use of antipsychotics in the analysed group of patients. Antidepressant and anticonvulsant effects have also been observed. Furthermore, it was shown that CBDs administered in mice with Dravet syndrome improve social behaviour, dysfunction of which is one of the central symptoms of autism spectrum disorder.