The invention relates to a method for preparing xylose by using squeezed waste alkali in the viscose fiber production process. According to the method, xylose finished products are obtained through work procedures of hemicellulose solution preparation, hemicellulose extraction, hemicellulose hydrolysis, neutralization and deacidification, preconcentration, decoloration, ion exchange, ordinary concentration, crystallization, separation and drying. When the technical scheme provided by the invention is adopted, harmful environment-pollution substances such as waste alkali and waste water generated in the viscose production process can be thoroughly eliminated, the standard of full-flow-process clean production can be reached, viscose production enterprises can also produce xylose in the viscose production process, the goal of environment protection is reached, and meanwhile, the waste reutilization is also realized.