Abstract: Overweight and obesity among children and adolescents have become a major public health problem, and the prevention and control strategies are shifting from traditional individual-based behavioral interventions toward systematic, multisectoral collaborative paradigms. Using a three-level nested model of individuals, the environment, and policies as the analytical framework, we systematically summarized in this review the connotation and evidence of Intensive Health Behavior and Lifestyle Treatment (IHBLT). We also analyzed the core challenges, including balancing weight reduction with growth and development, identifying sarcopenic obesity, conducting multi-component assessment of appropriate weight, and understanding the modulatory role of sleep health. The pathways for establishing a multisectoral collaborative system of prevention and control were discussed. On this basis, it was proposed that 3 major scientific questions should be prioritized in future efforts to prevent and control obesity among children and adolescents in China: (1) establishing a localized IHBLT dose-response model to address the challenges of adapting, to local cultural, resource, and technological contexts, the Western standard of 26 or more hours of face-to-face, family-based, multicomponent treatment over a 3- to 12-month period; (2) introducing metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) phenotyping for stratified assessment to avoid overtreatment of children with simple obesity; and (3) using longitudinal data from routine school physical examinations to develop dynamic growth trajectory early-warning algorithms, thereby shifting from single cross-sectional screening to individualized trajectory monitoring. This review aims to provide a reference for building an integrated, full-course management continuum encompassing prevention, screening, diagnosis, treatment, and rehabilitation and for advancing the focus from treating existing disease toward preventing disease before its onset.