Abstract: Grain security is a top national priority. The new grain security concept provides the logical starting point and fundamental principles for building a grain security policy support system in the new era. The emergence and evolution of this concept have ushered grain security support policies into a stage of systemic transformation. Centered on the new grain security concept, this study systematically examines the dynamic evolution of grain support policies across six dimensions: policy foundations, policy objectives, policy instruments, accountability mechanisms, implementation pathways, and policy perspectives. In addition, this paper also makes an overall assessment of the strategic opportunities in exploring the leading of the concept of all-encompassing approach to grain, drive of dual carbon goals, orientation of policy effectiveness, and stimulation of common prosperity, as well as realistic difficulties such as escalating climate change, weakness in integration of three chains, insufficient coordination of interests, and obstacles in green transformation on the basis of implementation achievements such as consolidation of grain production capacity, incentives for grain-growing entities, stronger resilience of the industrial chain, promotion of green transformation, governance shared by multiple subjects, and global grain security governance. To systematically improve the support policies for grain security and construct a higher level grain security system and greater resilience, this paper suggests expanding support channels to adapt to the concept of all-encompassing approach to food, strengthening climate adaptation resilience, consolidating the full-chain industrial security barrier, optimizing incentives for subjects combining with the goal of common prosperity, deepening green and low-carbon transformations, and coordinating international and domestic circulations.