Five different xylanases and a .beta.-D-xylosidase in the culture medium of A. niger were purified to homogeneity from 13-52-fold by a procedure of gel and hydroxylapatite chromatography. The strain was isolated from soil of the African equatorial forest. Gel chromatography of the purified enzymes indicated that 3 of the xylanases have MW of 31,000 and the other 2 xylanases have MW of 50,000. .beta.-D-Xylosidase has a MW of 78,000. The pH curves of the xylanases were quite diverse and showed pH optima ranging from 4.0-6.5. Characteristic action patterns were obtained for each of the purified xylanases by gel chromatography of the xylan digests on Bio-Gel P-2. The enzymes degraded arabinoxylan by an endomechanism, producing L-arabinose, D-xylose, xylobiose, and a mixture of branched arabinose-xylose and D-xylose oligosaccharides. All xylanases seemed to be capable of libertaing L-arabinose from either arabinoxylan or the arabinose-xylose oligosaccharides. Branched arabinose-containing D-xylose oligosaccharides were slowly hydrolyzed, so that these sugars accumulate in the digest. Two xylanases showed relatively broad substrate specificity and were able to degrade also crystalline cellulose. .beta.-D-Xylosidase showed optimal activity at pH 6.7-7.0 and at 42.degree. C. The Km for o-nitrophenyl-.beta.-D-xylopyranoside was 0.22 mM and xylotriose was hydrolyzed more rapidly than xylobiose.