Abstract: In winter time, phyllostachys praecox forest were covered with different organic material,several enzyme activities were tested regularly. It is concluded that enzyme activities of soil covered with bamboo leaves are rising with the day. At the end of experiment (on the Day 100) the activities of hydrogen peroxidase,sucrase,phosphatese,urease,protease are respectively 3.24,2.08,2.01,1.48,2.40 times as that of the original. Soil covered with rice straw or rice straw plus rice chaff,enzyme activities of hydrogen peroxidase,sucrase,phosphatese are growing until Day 75,but down afterwards till the end of experiment. As to urease and protease,there is almost no change in activities except a little down during the later experiment period.