Abstract: ObjectiveTo explore possible environmental factors influencing behavioral sexual dimorphism in preschool-age children.MethodsA self-designed questionnaire was used to collect information on ambient environment among the parents of 720 preschool-age children from 4 kindergartens in one district in Qingdao city,Shandong province;Pre-School Activities Inventory(PSAI)and Sensory Integrative Inventory were also employed simultaneously to assess behavioral sexual dimorphism and symptoms of sensory processing dysfunction(SPD)among the children.ResultsThe girls with SPD symptoms had significantly higher PSAI scores than those without SPD symptoms(41.78±6.56 vs.40.34±6.89,P<0.01).Significantly negative correlation was found between children's ages and their opposite sexual PSAI scores(r=-0.113 in the boys and r=-0.126 in the girls),respectively.The PSAI score of the children was positively correlated with their parents' educational levels(P<0.05 for linear trend test).Higher feminine PSAI scores were found among the children living in the area far from major traffic roads or being sensitive to multiple chemicals(P<0.05).ConclusionSensory integration in early childhood might be associated with the sexual dimorphism and daily living activities of themselves and environmental chemical factors might influence sexual dimorphism of the children.