Recombinant endo-beta-1,4-xylanase (Xyl-31rec, 31 kD, pI 8.2-9.3, the tenth family of glycosyl hydrolases) was isolated from the culture liquid of Penicillium canescens (strain with the amplified homologous xylanase gene) by chromatofocusing on Mono P and hydrophobic chromatography on phenyl-Superose. It is shown that the biochemical and kinetic parameters, substrate specificity, stability, and other properties of the recombinant and native enzymes are almost the same. It was found that Xyl-31rec can be used for biobleaching of cellulose, the recombinant P. canescens strains providing a high yield of extracellular Xyl-31rec (up to 800-900 U/ml of culture liquid) and not secreting cellulases.