ObjectiveTo investigate the oral health status of three to five year-old Uygur and Han children in Yining region of Xinjiang Uygur Autonomous Region, so as to provide scientific basis of corresponding countermeasures. MethodsA stratified, multistage and cluster sampling method was used to select 1 000 three to five year-old preschoolers from urban and rural districts in Yining region of Xinjiang Uygur Autonomous Region. The dental caries rate and oral health situation of included children by age, sex, nationality, and region were analyzed. ResultA total of 965 children were included. The response rate was 96.5%. The prevalence of deciduous dental caries was 81.24% with the mean DMFT score of 4.44. There were significant differences in levels of caries among different age groups, the prevalence of dental caries and mean DMFT score increased gradually as the children were growing up (P<0.05). The rate of filling teeth was 1.66%, and untreated caries was 98.34%. Maxillary deciduous central incisors and mandibular deciduous molar were most prone to decay. There were significant different oral hygiene status and malocclusion levels between the Uygur and Han, urban and rural districts, different age groups (all P values <0.05). ConclusionThe oral health status among three to five year-old preschoolers is not optimistic in Yining region of Xinjiang Uygur Autonomous Region. Integrated treatment and preventive programs are urgently needed.