In order to improve the performance of saccharification of Jerusalem artichoke stalk in bioethanol production, the hydrothermal pretreatment of stalk with H2SO3 catalysis and high-substrate consistency enzymatic hydrolysis were performed. Based on this work, the suitable pretreatment conditions, the high substrate consistency potential and the enzymes input lowering potential were determined. The results indicate that the suitable pretreatment should be carried out at 180℃ with 2% H2SO3 catalysis, by which the hemicellulose in stalk could be completely removed. Consequently, the maximum hydrolysis ratio of 90.0% could be achieved with 2.0% substrate consistency, 20FPU/g cellulose loading and 40CBU/g cellobiase loading. The high substrate consistency potential of pretreated Jerusalem artichoke stalk was suggested as 12% for enzymatic hydrolysis. The cellulase and the cellobiase input at this consistency could be lowered to 15FPU/g and 20CBU/g, by which the hydrolysis ratio of 88.3% could be achieved, with only 1.8% decrease compared with the maximum hydrolysis ratio. Correspondingly, the cellulase and the cellobiase loading is reduced by 25% and 50%, respectively.