In this study, a process for producing XOS from Sehima nervosum grass was developed. The grass contains 28.1% hemicellulose. NaOH and steam application yielded 98% of original xylan in contrast to 85% by KOH application. Hydrolysis of xylan with commercial xylanase caused breakdown into XOS comprising of xylobiose, xylotriose along with xylose. Response surface model (RSM) revealed highest xylobiose yield (11 g/100 g xylan) at pH 5.03, temperature 45.19 degrees C, reaction time 10.11 h with enzyme dose 17.41 U. Similarly for maximizing xylotriose yield, ideal hydrolysis conditions were pH 5.11, temperature 40.33 degrees C, reaction time 16.55 h with enzyme dose 13.20 U. A two step process encompassing xylan fractionation and enzymatic hydrolysis enabled XOS production from the S. nervosum grass. (C) 2012 Elsevier Ltd. All rights reserved.