The invention discloses a bamboo blasting high-boiling-solvent lignin preparation method and solves problems of difficulty in lignin extraction and separation, low yield and purity and difficulty in realization of continuous industrial production in the prior art. The method includes steps: extracting xylose according to a method disclosed in a patent with a publication number of CN106906262; mixing butanediol aqueous solution with materials obtained after xylose extraction, performing reaction in a continuous reactor, and discharging a mixture; filtering, sequentially washing filter residueswith butanediol aqueous solution and warm water, combining washing liquid with filtrate to obtain mixed solution, and drying filter residues to obtain coarse cellulose; adding water into the mixed solution, stirring to dissolve lignin out, filtering, washing a filter cake with hot water, and drying to obtain lignin. The method is simple in process and simple and convenient to operate, continuous industrial production can be realized, production cost is reduced, and high lignin yield and high purity are realized.