Porous silicon was prepared by electrochemical anodized method,and the porosity and film depth of porous silicon prepared under different anodized conditions as well as the effect of anodized conditions,sodium perchlorate concentration and storage methods on the explosion characteristics were studied. Results show that the porosity of porous silicon increases with the increasing of current density,and is stable when current density is 50 mA·cm^-2. With the increasing of hydrofluoric acid concentration,the porosity of porous silicon decreases; with the increasing of anodizing time,the porosity increases firstly and then decreases; the porosity reaches the maximum when the anodizing time is 30 min. Film depth is thicker when anodizing time is longer,and its growth speed is about 2 μm·min^-1. Porous silicon cracks on surface and contains silicon columns internal which are 40 μm in length and 2-3 μm in width. Porous silicon/NaClO₄ composite can explode when sodium perchlorate concentration is higher than 0.1 g·mL^-1 and the porous silicon is fresh or dipping in the ethanol within 7 days.