OBJECTIVES: To assess the relationship between health care system and economic factors and early childhood caries (ECC) data availability and prevalence. METHODS: We estimated ECC data for 193 United Nations countries from studies published between 2007 and 2017. We obtained other variables from the World Health Organization and the World Bank databases. We assessed association with ECC data availability by using logistic regression and with ECC prevalence by using linear regression. RESULTS: We included 190 publications from 88 (45.6%) countries. The mean ECC prevalence was 23.8% and 57.3% in children younger than 36 months and children aged 36 to 71 months, respectively. The odds of ECC data availability were significantly higher for countries with more physicians and more dentists. In children younger than 36 months, ECC prevalence was associated with universal health coverage (B = -6.56). In children aged 36 to 71 months, it was associated with growth of gross national income (B = 0.27). CONCLUSIONS: Countries with more physicians and more dentists were more likely to have ECC data. Among those with data, countries with higher economic growth had higher ECC prevalence.