Objective: To evaluate the relationship between excess body weight (EBW) and the prevalence of dental caries in preschoolers considering parental control regarding snack consumption. Material and Methods: An observational, population-based, cross-sectional study was conducted at Municipal Child Education Centers in the city of Curitiba, Brazil, involving a representative sample of 686 preschool children aged four to five years and eleven months and their parents/caregivers. Dental caries was analyzed using the dmft index. Weight and height were measured for the determination of the body mass index, which was categorized for each z-score range considering age and sex. Children with overweight or obesity were considered to have EBW. The assessment of nutritional status was performed with the aid of the WHO Anthro and WHO Anthro Plus programs. The data were analyzed using univariate and multivariate Poisson regression analysis with robust variance ( α = 0.05). Results: The children with EBW had a lower prevalence rate of caries, but this association lost its significance when adjusted by the other variables included in the multivariate model. In the multivariate regression analysis, household income per capita (PR=0.804; 95%CI: 0.665-0.972), child's age (PR=1.015; 95%CI: 1.001-1.029) and snack limits (PR=0.839; 95%IC: 0.732-0.962) were associated with a greater prevalence rate of dental caries. Conclusion: Excess body weight was not significantly associated with dental caries, whereas a lower parental limit regarding snack consumption by the children was independently associated with a higher prevalence rate of dental caries.