The invention belongs to the technical field of biomass energy and particularly relates to a lignocellulose biomass saccharifying method with mechanical activation cooperated with sodium hydroxide solid phase reinforcement. The lignocellulose biomass saccharifying method with mechanical activation cooperated with sodium hydroxide solid phase reinforcement comprises the following steps of lignocellulose biomass pretreatment, mechanical activation treatment, lignin elution and cellulose saccharification. By means of the method, the lignin content can be reduced, and invalid adsorption of lignin to cellulase is reduced; lignocellulosic structures are damaged, cellulose degree of crystallinity is reduced, and lignocellulosic chemical reactivity and accessibility of cellulase to cellulose are improved. The method has the advantages that high temperature and high pressure are not needed, the enzymolysis time is short, energy consumption is low, no corrosion is caused to equipment, and substances harmful to following fermentation stage are not produced.