Abstract: Objective To understand the current situation of caries among primary and secondary school students in Cangzhou City,provide a basis for scientific evaluation and targeted intervention. Methods From September to October 2023,a total of 29 067 students from 83 primary and secondary schools in 16 counties and districts of Cangzhou City were selected by stratified random cluster sampling method for physical examination,and the data were analyzed. Results The overall prevalence rate of caries among primary and secondary school students aged 6-17 years old in Cangzhou City was 38.28%. The prevalence rate of caries in male students（36.43%） was lower than that in and female students（40.38%）. The rates of caries of different genders were higher in urban areas than in suburban counties（all P<0.05）,and the differences were statistically significant. The prevalence rate of deciduous teeth was 30.71%,and the average caries was 1.01. The prevalence of permanent tooth caries was 19.60%,and the average caries was 0.45. The prevalence rate of caries and the caries loss rate of deciduous teeth and permanent teeth in different sex showed different characteristics with age. The caries prevalence rates of 7 year-old girls and 9,12 and 14 year-old boys and girls were lower than that of the whole country（all P<0.05）. The average caries of deciduous teeth in 7,9 and 12 year-old students and average caries of permanent teeth in 7,9,12 and 14 year-old students were lower than that of the whole country. Conclusion The prevalence rate of caries among primary and secondary school students aged 6-17 years old in Cangzhou City is not optimistic,so the prevention and control of caries among primary and secondary school students should be strengthened to effectively reduce caries prevalence.

Key words: Primary and secondary school students, Decayed teeth, Caries prevalence rate