Abstract: The aim of this study was to observe the number of major microorganisms and change trends during the corn silage processing. The corn silage in bottles was made by crosscutting of corn and rubbing stalk, the raw materials of corn silage were got and the silage samples at 0.5, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 15, 20, 25, 30, 35, 40, 45 and 50 days during silage processing were collected, the samples with aseptic water were soaked, and then the main microorganisms(lactic acid bacteria, yeast and mold) were cultured with selective culture medium. The results showed that the moisture content changed very little during the 60 days after the corn silage sealed. pH reduced to <4 at the 2nd day and then stayed at about 3.5. pH of corn silage was lower than that of rubbing stalk silage. The number of lactic acid bacteria increased rapidly and reached to the peak of 109 orders of magnitude at the 6th or 7th day, and later declined slowly and stabled at 107 orders of magnitude at 15th20th day. The number of lactic acid bacteria of corn silage with a peak at 6th day was higher than that of the rubbing stalk silage with a peak at 7th day. The number of yeast had fluctuations initially and reached the peak to 107 orders of magnitude, then reduced with the treating time prolonged. The number of yeast of rubbing stalk silage reduced rapidly and disappeared after the 40th day. But the number of yeast of corn silage increased within 12 hours at the beginning of silage and then reduced slowly, finally disappeared after the 50th day. The number of mold reduced sharply because of the shortage of oxygen after sealed, and it was not found after 11th day. The number of mold of rubbing stalk silage reduced sharply and no mold was found after 4th day, while the number of mold of corn silage reduced slowly and no mold was found after 11th day. In the process of corn silage, the number of major microorganisms decreased gradually with the treating time prolonged; rubbing was beneficial to make the corn silage.