Abstract: The concept of food component and its characteristics, content, principle, significance, as well as its improvement and the four development stages of diet history in human are discussed in the paper. The major works for the food component improvement at the present in China are proposed as follows: first,to do well the rational dietary of the population and guide the food consumption according to the principle of nutriology, second, to readjust the food types and raise total amount of foods, third, to improve the Chinese dishes as to meet nutritional needs, and fourth, to let the under-nourished peasants produce more foods as well as ensuring themselves nutritional balances, in order to get a good result for the food component improvement in China.