The effect of the soil inorganic nanometer particle(SINP)on several enzyme activity in the corn stalk decomposition process was deserved.The results suggest: The influence of SINP on enzyme activity was significant after the addition of SINP into the decomposing stalk,but the influence was various with the sorts of enzyme.All phosphatases activities were increased and increased significantly in the former and latter decomposing process and the same as to protease.The effect of SINP on urease was an increase trend in the whole process.However,the SINP previously increased invertase activity in the former and inhibited it in the middle-latter decomposing process.Therefore,enzyme activities in stalk decomposing process were increased by SINP.