OBJECTIVE To investigate the status of dental caries of deciduous teeth among preschool children in Shenyang city. METHODS According to the criteria recommended by the World Health Organization and The Second National Oral Health Investigation, the deciduous caries of 5375 preschool children aged from 3 to 6 years were clinically examined. The mean dmft and the prevalence of dental caries for each age group were calculated. The results were analyzed using SPSS11.0 software package for t test (to compare the difference between the two sample groups), one way ANOVA (to compare the differences among three and more sample groups) and chi2 test (to compare the rate of each group). RESULTS The prevalence of dental caries was 71.29%. The mean dmft score was 3.88. The prevalence of dental caries and mean dmft increased gradually as the children were growing up (P < 0.05).Dental caries of the upper teeth was significantly more common than that of the lower teeth (P < 0.01). Most caries were minor in degree of severity, and mostly lie in the occlusal and proximal surface. The filling rate was 10.82%.As the age increase, the filling rate increased, too. CONCLUSIONS Deciduous dental caries of preschool children was an important problem in Shenyang city, and the filling rate was very low. Necessary methods for early prevention of dental caries must be taken into consideration. Supported by Scientific Research Fund for College and University from Liaoning Provincial Education Bureau (Grant No. 20201316).