Grain freshness is affected by various factors in the environment during the process of storage, and its quality will change as time goes by. Therefore, the identification of freshness of grain is an indispensable and important in grain storage. However, in the grain industry, there has been no standard national method to indetify the freshness of grain. This paper summarizes common identification methods of the freshness of grain, and looks out to the future developments and researches, so as to provide references for people who work in the grain industry.