A strain of Bacillus sp. DSNC 101, isolated from soil, produced up to 305.0 units/ml of xylanase when grown on te medium containing 2.0% xylan, 2.0% yeast extract and 0.4% K2HPO4. The strain produced xylanase in the presence of xylan, soluble starch, rice straw, Avicel, maltose, and lactose as a sole carbon source, but the enzyme was not synthesized in the presence of xylose, glucose or arabinose. The crude xylanase preparation did not show hydrolytic activity towards cellulosic substrates and PNPX, a chromogenic substrate for $eta$-xylosidase. The temperature and pH optima for the xylanase production were 4$0^{circ}C$ and 8.0, respectively. Xylanase synthesis was repressed by glucose, but not by xylose. The hydrolysis products of xylan catalyzed with the culture filtrate were xylooligosaccharides such as xylobiose and xylotriose but xylose was not detected by tin layer chromatography.