Objective: To determine the current prevalence and severity of caries in primary dentition in a preschool population in 2 provinces in China, and to investigate the relationship between caries experience and sociodemographic factors, parental characteristics, dietary habits, and oral hygiene practice. Method and Materials: A cross-sectional survey was conducted on a representative sample of Chinese preschool children aged 3 to 5 years. Clinical examinations were carried out on 2,014 children using the method and criteria established by the World Health Organization. Structured questionnaires for information related to the sociodemographic background, oral hygiene practices, and dietary habits of the children were completed by their mothers. Results: Overall, 45% of children were caries free, and 14% had rampant caries. The mean dmft and dmfs values were 2.57 and 4.25, respectively. The caries prevalence and severity increased with age. The children from rural areas brushed their teeth less regularly and had a higher level of caries experience than those from urban areas. Significant predictors of caries experience were location, area, age, mother's education level, and consumption of fruit juice from a feeding bottle. Conclusions: These data indicate that a high proportion of young Chinese children had dental caries and that most decayed teeth were left untreated. The prevalence and severity of caries was associated with socioeconomic status and dietary factors in this sample of children. Keywords: caries, dietary habit, oral hygiene, rampant caries, social class