Background Autism spectrum disorder (ASD) is the most well-known neurodevelopmental disorder. Because there is no definitive biomarker for ASD, diagnosis is made based on the assessment of the patient’s behavior. The aim of this study was to reveal the effect of psychological evaluation of parents on the behavioral and social situations of individuals with autism. Materials and Methods A total of 94 individuals aged 3-18, consisting of 15 pairs of monozygotic (MZ) (ASD: 29, healthy: 1), 32 pairs of dizygotic (DZ) twins (ASD: 41, healthy: 23) and their parents, were included in the study. In addition to comparing autistic and healthy twins in terms of clinical and developmental data, social inadequacies, communicative limitations, repetitive interests, and limitations were evaluated in patients with MZ and DZ. While the Autism Spectrum Questionnaire (AQ) and Toronto Alexithymia Scale (TAS-20) tests were administered to the parents, Beck Depression Inventory (BDI) and World Health Organization Quality of Life (WHOQOL-BREF) tests were also administered to the mothers. RESULTS According to the developmental data of the individuals, significant differences were found between ASD and healthy individuals in terms of talking (p=0.00002) and toilet training (p=0.0003). In patients, it was determined that there was a relationship between the severity of the disease, repetitive interests and limitations (p=0.046) and speech (p=0.012). While there was a relationship between the WHOQOL-BREF subcategories applied to mothers and both AQ and BDI tests, statistical significance was also determined between the TAS-20 and BDI tests (p=0.016). CONCLUSION The effect of parents’ psychological states on individuals with autism has been revealed. We believe that the clinical examinations of the twins, the psychological evaluations of their families, and the psychological state of the parents in the ASD clinic are effective. Thus, it has been clearly shown that the family factor is also important in improving the clinic of individuals with autism.