Abstract: Objective To describe the caries status in 3~5 years old children in Jiangsu Province and to provide information support for oral health care．Methods Referring to protocols of the fourth national oral health survey, we used the method of multistage, stratified, equal capacity, simple random sampling to draw a sample of 1337 in Jiangsu Province. Subjects were from three different age groups (aged 3, 4 and 5), with 441, 455 and 441 children in each group. The dental caries in deciduous teeth were recorded using CPI probe. And then the prevalence, the mean dmft, the filling rate were calculated. Results The prevalence of dental caries in deciduous teeth in the three groups of aged 3, 4, 5 were 47.39%, 60.22%, and 71.43% respectively; the mean dmft were 2.22, 2.94, and 4.05 respectively; the filling rate were 0.72%, 1.72%, and 2.63% respectively. There were significant differences in the prevalence, the mean dmft and the filling rate among different age groups and among different regions. There was no significant difference in the prevalence and mean dmft regarding the gender in each group. The prevalence in the group of aged 3 in rural areas was higher than that in urban areas (P<0.01), while no urban and rural differences were found in the groups of aged 4 and 5. The mean dmft in the group of aged 4 in rural areas was higher than that in urban areas (P<0.05), while no urban and rural differences were found in the groups of aged 3 and 5. The Sic index of the three groups of aged 3, 4, 5 were 6.01, 7.44, and 9.03 respectively. The highest prevalence occurred on the upper middle incisors and the lower molars. The prevalence rate and mean dmft of 5?year?old children were higher than that in 2005, and the filling rate improved a little. Conclusions The 3?5?year?old children of Jiangsu Province had a high prevalence of dental caries in deciduous teeth. Prevention programs focusing on high risk population were urgently needed.

Key words: primary tooth, caries, oral epidemiology, cross-sectional survey