Although autism is now recognized as being very common (Buie et al., 2010) and as developing due to not only genetic but also environmental factors, there is insufficient epidemiological evidence on the relationship between autism and allergy. In this study, therefore, we attempted to clarify the association of environmental factors with autism and allergy using a population-based epidemiological study and to propose a newly developed screening method with improved validity by determining the relationship between ASD (autism spectrum disorders) subscales. We examined the association among autistic score from the Autism Screening Questionnaire (ASQ Japanese version), living environment factors, and allergic disease in 1407 children aged 3-5 years old. We recognized that children with higher ASD score have significantly higher prevalence of nasal allergy and associated with significantly factors of boy and first in terms of birth order and maternal smoking. In addition, nasal allergy were observed to be associated with "reciprocal social interaction", "language and communication", and "repetitive and stereotyped patterns of behaviors" as subscales of ASD. These results suggest that autism in children were closely related to allergy and environmental factors. Investigation of allergy symptoms in addition to subscale of ASD seem to enable more efficient screening of autism tendency at an earlier stage. (Contains 5 tables.)