In recent years, as the unseen changes in a century and the pandemic are intertwined, the increasingly complex and uncertain external environment aggravated the risk faced by Chinese food supply security. This paper is based on the perspectives of international geopolitical conflicts, frequent extreme events, concentration of domestic food imports, emergency guarantee mechanism of agricultural products, and food supply and demand structure under the new situation. It pointed out that the security of Chinese food supply is faced with such risks as worsening international food supply and demand imbalance, increasing food supply uncertainty and cost, increasing domestic food supply vulnerability, insufficient ability to resist risks, and escalating contradiction between food supply structure and consumers’ diversified demands. Based on the research and judgment of the current risks of food supply security, this paper proposed that first of all, we should strengthen the research and development of seeds and other key technologies to optimize the grain planting structure, and use new technologies to improve the comprehensive grain production efficiency and capacity for consolidating the foundation of food security. Secondly, the emergency guarantee system of important agricultural products should be established for ensuring the effective supply of important agricultural products under the new situation. Finally, we should strengthen Chinese food trade partnership, which could promote the high-quality development of China’s food trade and enhance the competitiveness of international food trade by promoting the distribution of food industry chain in the “Belt and Road” countries. In addition, we could make use of the Regional Comprehensive Economic Partnership (RCEP) to create a good grain trade pattern, and deepering agricultural cooperation with African countries. This paper provides a reference basis for ensuring the security of food supply.