Objective: This review summarizes evidence pertaining to the impact of the COVID-19 pandemic on the psychological health of children and adolescents with autism spectrum disorder (ASD). Materials and Methods: An electronic search was conducted using four major databases--PubMed, ScienceDirect, Web of Science, and Google Scholar. Using an umbrella methodology, the reference lists of relevant papers were reviewed, and citation searches were conducted. The study included articles written in English between January 2020 and March 2021 that focused on the psychological health of autistic children and adolescents. Results: All eight studies included in the final review were cross-sectional. Three of the eight studies were conducted in Italy, two in Turkey, and one study each in Portugal, Spain, and the United Kingdom, with a total of 1,407 participants. All studies used a mixture of standardized and non-standardized questionnaires to collect data. The total number of patients were 1407 at a mean age of 9.53 (SD = 2.96) years. Seven studies report gender; male 74.7% (657/880) and female 25.3% (223/880). The finding showed that behavioral issues in children and adolescents with ASD have significantly increased; 521 (51.9 percent) of the 1004 individuals with ASD presented with behavioral changes, including conduct problems, emotional problems, aggression, and hyperactivity. Some studies also found increased anxiety and difficulties managing emotions. Only one study reported clinical stabilization in children with ASD during COVID-19. Finally, 82.7% of families and caregivers of children with ASD (544 out of 658) faced challenges during COVID-19. Conclusion: Although the studies in this review suggest a general worsening of ASD children's clinical status, it remains difficult to draw definitive conclusions at this moment, with newer COVID-19 variants on the rise worldwide. During this difficult pandemic period, caregivers, families, and healthcare professionals are recommended to pay more attention to the ASD patients' health and care needs.