Abstract: The effects of green liquor pretreatment on the enzymatic hydrolysis of wheat straw for production of ethanol was investigated at different temperatures, total titrateable alkali (TTA) charges and sulfidity. Lignin can be effectively removed with the increasing amount of TTA charge and sulfidity in GL pretreatment while pulp yield drops with the increasing amount of TTA charge and sulfidity. The final pH was controlled to be lower than 9.5 in order to prevent the severe loss of carbohydrates and to ensure little silica dissolved in the black liquor. The pretreated materials were hydrolyzed by the enzyme cocktail which was a mixture of cellulase, xylanase and β-glucosidase to evaluate the improvement of sugar recovery. Compared with the cellulase loading of 5 FPU/g, sugar yield was significantly increased by the loading of 10 FPU/g. After 48 h enzymatic hydrolysis under a cellulase loading of 10 FPU/g pulp, the total sugar yield of pulp pretreated by 8 % TTA and sulfidity 40% at 130 ℃ was the highest among all pretreated pulps, and the highest enzymatic hydrolysis sugar recovery was 73.1 %. These results provided evidences that the enzymatic hydrolysis efficiency of wheat straw can be significantly improved by GL pretreatment.