Child assessment practices in English and Korean preschools were compared by analysing data from interviews with educators, examples of child assessment, and official documents from each country. Child assessment in England was systematically implemented and characterised by several methodological and procedural strengths, whereas assessment in Korea was fragmented and unsystematic. However, the English system led to burdensome workloads for educators, the ranking of children and institutions, and practices that contradicted developmentally appropriate principles. Authorities governing kindergartens and childcare centres in Korea need to develop a uniform framework, tools, and guidelines for child assessment and to improve the structure of the early childhood education and care (ECEC) via financial support.