Abstract: The effect of supplying phosphorus on adsorption and desorption action of silicon in paddy soil was studied. The results showed that supplying phosphorus to the soil decreased the amount of adsorption for silicon because of competitive between silicon and phosphorus,and increased silicon desorption and desorption rate in soil. This was, on one hand application of phosphorus reduce silicon adsorption, and other hand enhanced easily desorbed silicon content because of decreased bonding energy of silicon. Application of phosphorus produced the pushing action for silicon adsorption. This opinion is proved out by successive desorption experiment further.