Soil is a major carbon reservoir on Earth, and enhancing soil carbon sequestration capacity is of great significance for mitigating climate change, improving soil health, and ensuring sustainable agricultural development. This paper reviews the policy actions of international organizations and major countries; summarizes and analyzes the three technical paths of soil carbon sequestration: biological, chemical, and physical, as well as their integrated models; combines literature topic clustering analysis to summarize research themes such as carbon cycling in forest and agricultural ecosystems, synergistic emission reduction through farmland management, and regulation via vegetation restoration and biochar application; and further reviews important advances reported since 2024.The results indicate that multi-pathway synergy and system-level integration represent critical trends for enhancing soil carbon sink capacity. Continuous advances in biological process regulation, material optimization, and structural stabilization mechanisms provide new perspectives for achieving long-term and stable carbon sequestration. Nevertheless, significant challenges remain, including insufficient quantitative understanding of underlying mechanisms, constraints related to carbon saturation and stability, and the lack of unified accounting standards. Future research should strengthen multi-scale mechanistic studies and policy coordination to promote large-scale implementation of soil carbon sequestration technologies.