Abstract: Plackett-Burman and response surface analysis methods were applied to optimization of solid-state fermentation medium for producing biological pesticide by means of Bacillus thringiensis stimulated by the artificial pressure period. The significant influence factors of medium components on production of biological pesticide were evaluated by SAS system in brewer’s grain as main raw materials. The result of optimization showed by response surface methodology that the suitable medium components should be brewer’s grain 100g, corn meal 2.19g, soybean 15.41, KＨ2PO4 0.22g. Under the optimal conditions, the experimental values agreed with the predicted values. As the result, the activity of biological pesticide was 8563IU/mg.