Cereal protein has been extremely difficult to purify and characterize owing to their heterogeneity, poor solubility and tendency to polymerize. In order to have a full understanding of structure and function in cereal protein, to realize the separation and purification of grain protein, the composition and characteristics of cereal proteins were introduced briefly, introduced the research progress comprehensive recitation on principle and model of the grain protein purification domestic and overseas in recent years. The future research prospects of cereal proteins were put forward as well.