NOVELTY - Lignocellulosic biomass is processed by performing N-stage acid hydrolysis of lignocellulosic biomass raw material in reaction kettle by preparing acid solution, adding lignocellulosic biomass raw material and acid solution into 1st acid hydrolysis reaction kettle, discharging acid solution in 2nd acid hydrolysis reaction kettle, discharging acid solution in 3rd acid hydrolysis reaction kettle, discharging acid solution in N-stage acid hydrolysis reaction kettle, and obtaining final pentose solution and acid hydrolyzed slag, wherein 1st stage hydrolysis reaction time is 1-4 hours.    USE - Method of processing lignocellulosic biomass for ethanol production.    ADVANTAGE - Hydrolysis reaction is performed over a short period of time, generation of furfural and acetic acid is prevented, hemicellulose is easily removed, extraction rate of cellulose is improved, and damage to lignin and cellulose is prevented.    DETAILED DESCRIPTION - Lignocellulosic biomass is processed by performing N-stage acid hydrolysis of lignocellulosic biomass raw material in reaction kettle by preparing acid solution, adding lignocellulosic biomass raw material and acid solution into 1st acid hydrolysis reaction kettle, discharging acid solution in 2nd acid hydrolysis reaction kettle, discharging acid solution in 3rd acid hydrolysis reaction kettle, discharging acid solution in N-stage acid hydrolysis reaction kettle, and obtaining final pentose solution and acid hydrolyzed slag, wherein 1st stage hydrolysis reaction time is 1-4 hours, reaction time for each stage of hydrolysis reaction is gradually reduced by 0.25-1.5 hours, and N serves integer, using cellulase to carry out enzymolysis of acid hydrolyzed residue to obtain glucose solution and enzymolysis residue, processing enzymolysis residue by alkali solution, extracting lignin, performing alkaline hydrolysis to obtain hydrolysis residue, and repeating enzymolysis and alkaline hydrolysis steps to further extract lignin.    DESCRIPTION OF DRAWING(S) - The drawing shows a flowchart of the method of processing lignocellulosic biomass. (Drawing includes non-English language text).