Background Decayed teeth are harmful to childrens growth and development and can severely jeopardize their health.This study was set out to investigate and analyze the prevalence of dental caries in preschool children in Shanghe County in Shandong Province,China,and provide new insights into potential prevention and treatment strategies.Methods Based on the random sampling method,we performed dental examinations of children aged 2 to 6 years in kindergartens of Shanghe County.The prevalence of caries,the average number of decayed teeth per capita as well as the constituent rates of decayed,missing and filled teeth were determined retrospectively.SPSS software was used for data analysis.Results Dental caries were found in 1088 out of 2052 children from 56 kindergartens.The total number of decayed teeth was 4487 with a prevalence of 53.02%.The average number of decayed teeth per capita was 2.187,and the filling rate was 0.29%.There was no statistical difference in the prevalence of caries between boys and girls though there were significant differences between different age groups.The prevalence of decayed teeth as well as the mean number of decayed teeth infected per capita increased with age.In addition,urban children had a higher prevalence than those from rural areas (P ＜0.01).Conclusions The prevalence of decayed caries among kindergarten children in Shanghe County was high,suggesting that more emphasis should be put on improving oral health education with priority given to prevention.Further efforts should be made to increase the decayed caries filling rate.