Abstract: The content of total and available silicon in soil because of the forming process in south china are lower than that need to plant, study on silicon yield effect of peanut has great significance. The results of field trait are showed bellow: there is distinct effect of increasing yield after silicon is employed to soil ,and the greatest increasing effect is in legumen forming stage, 13.5%~25.6%, 20.1% by average. The recommend quantity of silicon in tropic brick red soil is 30kg/hm2 by analysis the cost and employing effect. To hundred-pod weight and hundred-seed weight, there are different results in different stage employing, but the best effect is the level of 30kg/hm2. There is increasing effect of hundred-pod weight employed only in legumen forming stage and with the level of 30kg/hm2, and the level of 30kg/hm2 also have increasing effect for hundred-seed weight in acicula forming and legumen forming stage. Foundation fertilizer with 30kg/hm2 level increasing the quantity of per plant; employing silicon has no significant effect on fat concentration, so silicon is applicable to edible species. Employing silicon make significant descend of plant nitrogen, significant increasing of plant phosphorus only with level of 90kg/hm2 applying before planting, decreasing of that only with level of 150kg/hm2 employing in legumen forming period, and no distinct effect with others levels. Comprehensive effect of plant potassium, and that should do better in future.