NOVELTY - Preparing fuel ethanol by fermenting cellulose hydrolysis solution with immobilized mixed strain comprises inoculating mixed strain of immobilized Pachysolen tannophilus and Saccharomyces cerevisiae into diluted acid hydrolysis solution, fermenting it in a fed-batch fermentation mode.    USE - The method is useful for preparing fuel ethanol by fermenting cellulose hydrolysis solution with immobilized mixed strain (claimed).    DETAILED DESCRIPTION - Preparing fuel ethanol by fermenting cellulose hydrolysis solution with immobilized mixed strain comprises inoculating mixed strain of immobilized P. tannophilus and S. cerevisiae into diluted acid hydrolysis solution, fermenting it in a fed-batch fermentation mode, where it specifically comprises: acclimatizing P. tannophilus and S. cerevisiae at the same time, where the percentage of hydrolysis solution in the culture medium increases along with the increase of the acclimation time by 20-50%; acclimatizing them till the culture medium completely becomes hydrolysis solution, inoculating the acclimation cultured P. tannophilus and S. cerevisiae into 3% of calcium alginate solution according to a ratio of 1:1, injecting it into 2% calcium chloride (CaCl2) aqueous solution and curing them for 2-6 hours, washing the calcium alginate gel ball (with diameter at 2-3 mm) with aseptic water, transferring them into 1% of aluminum sulfate solution, curing it at 0-4 degrees C for 12-24 hours to obtain gel ball of immobilized mixed strain; placing the gel ball of immobilized mixed strain into proliferate culture medium to be propagated and cultured at 28-35 degrees C at 100-150 revolution/minute for 20-48 hours, after proliferation, filling 20-50% of immobilized gel ball into fermentation culture medium of xylose cellulose hydrolysis solution with an initial sugar concentration of 3-15%; regulating the pH value to 3.0-7.0, shaking and fermenting it at 28-35 degrees C at 100-150 revolution/minute, after 12-48 hours, recharging fresh hydrolysis sugar solution for performing a fed-batch fermentation; where the acclimation culture medium comprises 10-50 g/L of xylose, 10-50 g/L of glucose, 2.5 g/L of urea, 5 g/L of yeast extract, 5 g/L of ammonium sulfate ((NH4)SO4), 2 g/L of potassium dihydrogen phosphate (KH2PO4), 1 g/L of magnesium sulfate heptahydrate (MgSO4.7H2O); culturing it at 30 degrees C at 160 revolutions per minute (rpm), increasing the percentage of hydrolysis liquid by 5-40%, where the acclimation in each batch is 18-24 hours and the total batch number is 6-24, the inoculation amount of the microzyme liquid is 10-20%.