Objective To analyze the current situation and influencing factors of sensory integration dysfunction (SID) among preschoolers in Chengdu. Method A total of 781 children from 2 kindergartens in Chengdu were surveyed with Children Sensory Integration Ability Assessment Scale and children basic information questionnaire. Results The incidence of SID in preschoolers in Chengdu was 38.28%,among which there were 234(29.96%) children with mild SID and 65(8.32%) with serious SID.There were significant differences among children with SID and normal children in sex (χ²=15.41,P<0.05).Incidence of SID among boys(23.05%)was higher than that among girls(15.24%).The influencing factors of SID among preschoolers were sex,gender,living area,gestational age at delivery,mothers' vaginal bleeding history during pregnancy,parents' educational attitude and parents' educational background. Conclusions SID is the prominent problem among preschoolers in Chengdu.It is influenced by biological and social factors.Parents and teachers should pay more attention to prevent it earlier.