Objective   To examine the prevalence of autism among 2 – 6 years children in kindergartens in Chongqing city.

  Methods   Totally 7 800 children aged 2.5 – 6 years were selected from ordinary kindergartens in 6 districts of Chongqing municipality. First, all the participants were primarily screened with Social Responsiveness Scale (SRS) by nursery teachers; then the children with positive primary screening results were then rescreened with Autism Behavior Checklist (ABC) and Childhood Autism Rating Scale (CARS) by medical personnel in local hospitals; finally the children suspected with autism spectrum disorders were diagnosed by experts based on the criterion of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V).

  Results   Among the 6 212 children with valid information, 282 were positive to autism spectrum disorders, with the positive rates of 4.5% in the primary screening and 10.63% in the rescreening. Totally 22 autism cases (17 boys and 5 girls) were diagnosed and the overall autism prevalence rate was 3.54‰; the prevalence rate among the boys was significantly higher than that among the girls (5.14‰ vs. 1.72‰, t = 5.43; P < 0.01); the prevalence rate was 3.35‰ and 4.18‰ in the urban and rural children, without significant difference (t = 0.19, P > 0.5); the autism prevalence rate was 5.31‰ among the children aged 2 – < 4 years and 2.53‰ among those aged 4 – 6 years.

  Conclusion   The prevalence rate of childhood autism in Chongqing municipality is slightly higher than that reported in other regions in China. A system for early screening, diagnosis, and rehabilitation of childhood autism needs to be established.