Aim: To evaluate the association between dental caries and nutritional status in a group of Brazilian schoolchildren, from Manaus. The studied population consisted of 197 students (10–12-year-olds) from public schools at Manaus, Amazonas, Brazil. Materials and methods: A clinical examination was carried out and the decay-missing-filled-teeth index for primary and permanent teeth (dmft and DMFT) was used to evaluate dental caries. Body mass index Z-score was calculated using variables such as individual height, weight, age, and gender. The nutritional status was classified as underweight, eutrophic, overweight, and obese. One-way ANOVA and Tukey’s posttests were used for means’ comparison between groups. The established alpha was 5%. Results: Eighty-one (41.1%) children were caries-free. Five (2.5%) children were underweight; 127 (64.5%) were eutrophic; 49 (24.9%) were overweight; and 16 (8.1%) were obese. The mean dmft/DMFT index was 1.67 (2.05). Obese children had more caries experience than eutrophic and overweight children (p < 0.05). Conclusion: Our study demonstrated that dental caries is associated with obesity in school children from Manaus.