Abstract: The food preferences and harm of Sitophilus zeamais Motschulsky and Callosobruchus chinensis were studied in this paper. The results showed that the selectivity and harm of S. zeamais to waxy maize, sorghum and wheat were higher than that to coin seed and common corn. The S. zeamais like higher starch food. The egg laying amount of C. chinensis on the black beans, red bean and green bean were higher, which were 78.75 eggs, 77.75 eggs and 75.75 eggs, respectively, but on the great white kidney bean was 0 egg. Therefore, in order to reduce the harm to the corn caused by the two kinds of insect, we proposed that the high content of starch grain should be stored separately and the great white kidney bean should be used as the cover on the other beans.