Coarse xylan were obtained by alkali extraction from super rice straw, then xylooligosaccharide were prepared by xylanase hydrolysis from coarse xylan. The enzymatic hydrolysis conditions were optimized by orthogonal array test, and the main component of enzymatic hydrolysate was analyzed by the high performance liquid chromatography (HPLC). The results indicated that the optimal parameters were as followed:〖JP+1〗the temperature 50 ℃, the initial pH 5.0, volume of enzyme 4%, the XOS yield was 13.5% on this condition. The HPLC analysis showed that the major composition of enzymatic hydrolysate was mainly xylobiose and xylotriose, only a small amount of monosaccharieds. This is beneficial to the purification of the subsequent oligosaccharides, and meet the requirements of the preparation of oligosaccharides.