Abstract:In recent years, the probability and frequency of international major emergencies are on the rise, which have threatened the global food security. The study decomposes the food supply chain into production section, consumption section, and circulation section; and then analyzes the risks of food security in each section when facing the major emergencies. In the production section, major emergencies restrict the inputs of labor and agricultural production materials, limiting food supply directly. In the consumption section, major emergencies usually increase the food price and decrease the resident income, and thus, decline the purchasing power of food and exacerbate the food crisis. In the circulation section, major emergencies may lead to the block of domestic food transportation and the interruption of international trade, which mismatches the food production and food consumption. In addition, the study puts forward that China's high grain self-sufficiency rate not only ensures Chinese food security, but also contributes to the global food security. The suggestions are proposed in the end to Chinese and global food security, respectively.