Background: Providing enriched learning environments is important to stimulating children's development in early childhood. Early child-care policymakers in many states in the US have adopted Quality Rating and Improvement Systems (QRIS) as a way to verify quality of child care and to support children's school readiness. Objective: The purpose of this study was to examine associations between QRIS, a statewide government-funded early childhood care and education policy which integrates structural quality of child-care, and children's cognitive skills. Methods: A sample of randomly selected 313 children (mean age = 54.9 months, SD = 6.7) from 36 QRIS-participating early child-care programs was included in this study. Results: Multilevel analysis with a latent variable (i.e., observed cognitive skills consisting of vocabulary, phonological awareness, and mathematical skills) revealed that children in the highest level of QRIS programs demonstrated better cognitive skills after controlling for child demographics, and home and neighborhood environments. In addition, QRIS moderated a negative association between family socioeconomic risk and children's cognitive skills. Conclusions: The results suggest that policymakers may expect positive returns on QRIS investments in terms of children's early cognitive achievements that support their school readiness in later life.