Food Security is a leading issue in global governance since the end of the World War II. The Food and Agriculture Organization of United States defined the defined this concept in the 1974 for the first time. Thereafter，the definition of food security evolved fast toward higher standard，consisting in the four pillars of availability，access，utilization and stability. In the COVID-19 pandemic of 2020，agency and sustainability are newly added into the definition to amend the shortage of global food governance. The methods most commonly used by UN organizations to measure the global food security are SDG Monitoring Framework Target 2 （SDG2） and Integrated Food Security Phase Classification （IPC）. According to these methods，the global food security deteriorated slowly since 2014 and the COVID-19 pandemic poses as an extremely dangerous threat to the already fragile situation. It’s not only the developing countries but also the developed ones are facing food insecurity，which originates from the inequity of income distribution instead of insufficient food production. The lower income countries and poor people are always suffering from hunger and malnutrition in an international society in which food supply is more than enough for some decades. Now COVID-19 has damaged the world economy severely and make the global food insecurity even more urgent. To enhance the global food security，the only answer is a mixture of advanced agriculture，fully-fledged social service and fair income distribution.