By analyzing the storage rules of silicon type delay composition and characterizing the surface oxidation film of silicon powder under different conditions by Electron Spectroscopy for Chemical Analysis(ESCA),it was concluded that the ultimate reason for the drift of delay time of this composition was the generation of oxidation film between the combustible agent and the oxidation agent during the course of storage,and the delay time was prolonged. By increasing the grind time of silicon powder,the delay precision of this composition was improved. With the method of high-temperature accelerated aging,the diffusing dynamic balance of interface between the combustible agent and the oxidation agent achieved,then the delay precision and the storage stability of this composition enhanced.