ObjectiveTo investigate the caries status of the first permanent molars in urban and rural children aged 10-12 in Chongqing and analyze the related factors in order to provide a theoretical basis for the prevention and treatment of children’s caries and targeted suggestions for oral health education.MethodsA multi-stage, stratified, cluster, and random sampling method was used to extract 5 057 children from 18 schools in three districts and three counties in Chongqing for oral health examination and questionnaire survey from March to May 2018.ResultsThe total caries rate of the first permanent molar was 39.2%. The decayed-missing-filled tooth was 0.84±1.20. The rate of filling teeth was 3.4%. The rate of pit and fissure sealing was 6.1%. The prevalence of the first permanent molars was significantly different between men and women, between urban and rural areas, between only children and non-only children, and between ethnic minorities and Han nationality (PPConclusionThe first permanent molars of children aged 10-12 in Chongqing have a high rate of caries but low rates of pit and fissure sealing and dental caries filling. The difference between urban and rural areas is large, children’s oral health knowledge is scarce, and children have bad oral hygiene behaviors and eating habits. Children’s oral health education must be strengthened, oral health preaching must be implemented in schools, the oral health knowledge of children in school must be improved, and urban-rural differences must be minimized.