This chapter provides a comprehensive and critical review of educational policies and empirical research on young children’s transition from kindergarten to primary school in the People’s Republic of China in the twenty-first century. It identifies a notable shift in policy, moving from a model where kindergartens were solely responsible for preparing children for primary education to a collaborative approach involving kindergartens, primary schools, and families to ensure a smooth transition. The Ministry of Education has also introduced a series of ‘de-schoolification’ policies, advocating a holistic view of school readiness that encompasses physical, mental, life, social, and learning adaptations. In line with these policy changes, empirical research has begun to challenge the traditional emphasis on cognitive development as the primary indicator of school readiness. While most research continues to rely on quantitative studies that use standardised measures to assess school readiness, there is a growing body of qualitative research exploring diverse perspectives, including those of children themselves. Based on this review, the chapter proposes five key principles to guide future research, practice, and policymaking in supporting children’s transition to primary school in China.