The study aimed to investigate the role of Toxoplasma gondii in causing autism and included 100 autistic patients from different governorates for the period from January to June of the year 2022. The results of the serological analysis showed that 8 of them were infected with toxoplasmosis by 8%, The results of the statistical analysis showed that there were no clear significant differences between the number of autistic patients with toxoplasmosis and their areas of residence at the level of probability (P > 0.05). Genetic variation (mutation analysis) was found in human mitochondrial CoxI gene among autistic patients, NCBI reference samples from one or two mutations, and the total percentage of genetic variation ranged from 2.08-1.04% , while genetic variation (mutation analysis) was found in The human mitochondrial gene Nad1 between autistic patients, healthy subjects and NCBI-Genbank reference samples had from one to two mutations in a proportion of total genetic variance that ranged 1.3-2%.