55 Xylanase-producing bacteria from the different sources of soil samples through the transparent circle method a high molecular weight xylanase-producing bacteriaby liquid fermentation and SDS-PAGE zymogramanalysis.Through single factor experiment and response surface analysis,the factors affecting the enzyme production fermentation optimizedthe best enzyme production fermentation conditions :carbon source(corn cob powder) 0.8%,nitrogen source(beef paste) 1%,initial pH value of 7.2,culture temperature 30 ℃,rotational speed of 158 r/min,of 2%,the fluid volume 50 mL.Under the optimized condition,the enzyme activity reached 44.12 U/mL after fermentation,which 4.36 times higher than before optimization.