In this paper,butanol was prepared from the enzymatic hydrolysate supermatant of steam- exploded cornstover,with Clostridium acetobutylicum as the experimental bacterium. Then,the effects of supermatant concentra-tion,initial pH value and microbial inoculation quantity on butanol yield were investigated,and the optimal dosagesof nutrient elements were determined by orthogonal test.The results show that,under optimal conditions,that is,asupermatant sugar content of 57.5g/L,an initial pH value of 6.3,an inoculation quantity of 6%,a fermentationtemperature of 37 ℃,and a nutrient elements addition of yeast extract 0.8g/L + CH₃ COONH₄ 6. 0g/L + KH₂ PO₄ 0. 5g/L + nicotinamide 0.25g/L,the butanol yield is up to 9.726g/L.Moreover,it is also found that there existsome inhibitors for the solvent production from steam- exploded corn stover enzymatic hydrolysate,and that a smallamount of nicotinamide may effectively promote butanol production.