The molasses, rice bran and yeast are used as variable factors in the study of the protein change in silage food. The applied of 23 factorial is used in the experiment and the statistical programming is used in analysis. The results show that the appropriate factors of molasses, rice bran and yeast are 5 gram, 5 gram and 2 gram, respectively. The appropriate mixture contains the protein of 4.250% in the silage food.