China’s grain production has been increasing for 11 years,up to 0.6 billion tons in 2014.Some researchers hence argued that grain in China is oversupplied.Meanwhile,there are voices proposing that agricultural subsidies should be removed and farmland should be permitted for full marketization.This study aims to do a reassessment in 4 directions:(1) The concepts of “Food Security”,“Grain Security”,and “Food Safety”; (2) The methodologies and criterion for assessing market equilibrium; (3) The dynamics of market equilibrium for grain in history; (4) The uncertainty and risks for grain supply in future.The results conclude that China is suffering from shortage rather than overcapacity for grain production.Tight balance is a pseudo equilibrium under continuous support by Chinese governments.Current grain market is imbalanced rather than “tight balanced” with strong intervention and distortion.As a rapid developing nation and economy,China’s demand and supply for grain and food are changing dynamically.Imbalance in the short term is trending to relatively balance in the long term.It is of great importance that Grain Security should be replaced with Food Security as new agricultural strategies in next decades.In sum,under current circumstances,it is necessary to take caution on judgement of “excessive grain” which may do harm to national security and economy.