Abstract: It has been found that different pretreatment of corn stover produces varying quantities of reducing sugars. Therefore, this study experimentally investigated the optimum conditions with respect to concentration of acetic acid, temperature and time. Response surface methodology (RSM) was employed for the analysis of the simultaneous effect of acid concentration, pretreatment temperature and time on the resulting total reducing sugar concentration obtained. A three-variable, five-level Central Composite Rotatable Design (CCRD) of experiment was used to develop a statistical model for the optimization of the process variables.