NOVELTY - Producing fuel ethanol using straw lignocelluloses as raw material, comprises: crushing the straw lignocelluloses to obtain straw lignocelluloses powder; centrifuging the straw lignocelluloses powder to obtain straw powder; adding lignocelluloses into the straw powder, stirring and hydrating to obtain cellulase hydrolyzed and saccharified hydrolysates; fermenting the ethanol in the fermenting tank and reducing the temperature of cellulase hydrolyzed and saccharified hydrolysates to 35 degrees C, adding yeast (2 g/l), performing the constant temperature fermenting reaction, and stirring.    USE - The method is useful for producing fuel ethanol using straw lignocelluloses as raw material.    ADVANTAGE - The method: uses rich raw material; is economical; has high hydrating efficiency; and yields fewer side product and high ethanol.    DETAILED DESCRIPTION - Producing fuel ethanol using straw lignocelluloses as raw material, comprises: (a) crushing the straw lignocelluloses in a crusher, sieving with 80 mesh screen and drying at 55 degrees C to obtain straw lignocelluloses powder; (b) taking the crushed and dried straw lignocelluloses powder, adding sodium hydroxide solution (1 wt.%), controlling the solid and liquid ratio as 1:20, stirring evenly, insulating for 50 minutes under the temperature of 121 degrees C and the pressure of 0.2 MPa, cooling to room temperature, adding distilled water, centrifugally separating in a centrifuge, drying the centrifuged straw deposit at 105 degrees C, crushing the deposit to 80 meshes and drying at 55 degrees C to obtain straw powder; (c) adding cellulase into the straw powder, stirring and hydrating for 48 hours at 40 degrees C when the pH value is 4.5 to obtain cellulase hydrolyzed and saccharified hydrolysates, where the addition of cellulose is 15 filter paper unit (FPU)/g straw powder; (d) fermenting the ethanol in the fermenting tank and reducing the temperature of cellulase hydrolyzed and saccharified hydrolysates to 35 degrees C, adding 2 g/L yeast, performing the constant temperature fermenting reaction, where the feeding amount of nutrition liquid is 10 ml nutrition liquid/l reaction liquid, the pH value is 4.5, and stirring, where the fermenting period is 48 hours.