Aims: To determine the associations between COVID-19 school closures and school readiness skills for Chinese kindergarteners. Design: We utilized the natural experimental condition created by local COVID-19 outbreaks in 2022 (Study 1) to compare school readiness skills of children whose kindergartens were closed for 5 months (Group 1) with children whose kindergartens stayed open (Group 2). We further compared the school readiness skills of one pre-COVID-19 cohort (Cohort 2019) with one COVID-19 cohort (Cohort 2021) from a fifth kindergarten (Study 2). Samples: For Study 1, Group 1 included 445 children and Group 2 included 584 children aged 4-6 years. For Study 2, Cohort 2019 included 156 children and Cohort 2021 included 228 children aged 3-6 years. Measures: For both studies, survey data on four school readiness skills were collected from parents. Additionally, Study 1 collected parental locus of control data from parents. Results: Controlling for covariates, Study 1 revealed that Group 1 and Group 2 did not differ in terms of language and emergent literacy or approaches to learning. However, Group 1 scored lower than Group 2 on health and well-being and arts and imagination. Study 2 revealed that Cohort 2021 scored higher than Cohort 2019 on language and emergent literacy but lower on the other three skills. Conclusions: The associations of COVID-19 school closures with Chinese children's school readiness skills were not uniform, with a positive relation with language and emergent literacy and negative associations with health and well-being, approaches to learning, as well as arts and imagination.